中尺度与纳米尺度物理

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[1] arXiv:2508.21089 [中文pdf, pdf, 其他]

标题： 声子散射引起的室温量子线性磁阻 显示英文标题

标题： Phonon-scattering-induced quantum linear magnetoresistance up to room temperature

Nannan Tang, Shuai Li, Yanzhao Liu, Jiayi Yang, Huakun Zuo, Gangjian Jin, Yi Ji, Bing Shen, Dingyong Zhong, Donghui Guo, Qizhong Zhu, Zhongbo Yan, Haizhou Lu, Jian Wang, Huichao Wang

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 强关联电子 (cond-mat.str-el)

在高温下实现量子输运效应长期以来引起了研究人员的兴趣，因为这有助于揭示新的物理现象并开发量子器件。 在本工作中，我们在强磁场（高达60 T）下，在40-300 K的高温下，报告了在Weyl半导体碲中显著的量子线性磁阻（LMR）。在高磁场下，Weyl带的最低和第一 Landau 能级之间存在较大的能隙，这抑制了热激发并在高温下保持了 Landau 量子化。 只要多数载流子保持在最低的 Landau 能级，而不需要单色性，就可以观察到 LMR，使其能够持续到室温。 LMR 斜率与温度之间的反比关系提供了明确的证据，表明量子 LMR 源于量子极限下的高温声子散射，首次证明了近五十年前的一个理论预测。 这项研究突出了电子-声子相互作用的关键作用，并揭示了一种创新的量子机制，以实现高温 LMR，这与以前的发现有根本的不同。 我们的结果填补了对声子介导的量子极限物理理解的空白，并确立了在高温下强磁场作为探索新颖量子现象的有前途的平台。 显示英文摘要

The realization of quantum transport effects at elevated temperatures has long intrigued researchers due to the implications for unveiling novel physics and developing quantum devices. In this work, we report remarkable quantum linear magnetoresistance (LMR) in the Weyl semiconductor tellurium at high temperatures of 40-300 K under strong magnetic fields up to 60 T. At high fields, the Weyl band features a large energy gap between the lowest and first Landau levels, which suppresses thermal excitation and preserves Landau quantization at high temperatures. The LMR is observed as long as majority carriers remain in the lowest Landau level without requiring monochromaticity, allowing it to persist up to room temperature. The inverse relationship between the LMR slope and temperature provides clear evidence that quantum LMR originates from high-temperature phonon scattering in the quantum limit, firstly demonstrating a theoretical prediction made nearly fifty years ago. This study highlights the key role of electron-phonon interaction and reveals an innovative quantum mechanism for achieving high-temperature LMR, fundamentally distinct from previous findings. Our results bridge a gap in the understanding of phonon-mediated quantum-limit physics and establish strong magnetic fields at high temperatures as a promising platform for exploring novel quantum phenomena.

[2] arXiv:2508.21234 [中文pdf, pdf, 其他]

标题： 探索Co、Fe和Ni参考层在铁磁自旋阀中单脉冲全光翻转的应用 显示英文标题

标题： Exploring Co, Fe, and Ni Reference Layers for Single-Pulse All-Optical Reversal in Ferromagnetic Spin Valves

Jun-Xiao Lin, Yann Le Guen, Julius Hohlfeld, Jon Gorchon, Grégory Malinowski, Stéphane Mangin, Daniel Lacour, Thomas Hauet, Michel Hehn

评论： 14页，4图

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall)

我们通过系统比较由纯Co、Ni和Fe组成的参考层，研究了超快激光脉冲在铁磁自旋阀中引起的磁化翻转过程。 为了克服由于参考层材料和厚度变化而引起的垂直磁各向异性的损失，我们设计了面内磁化的自旋阀。 虽然对于所有三种元素都观察到了反平行到平行的切换，但只有使用Co参考层时才会发生平行到反平行的切换，而在Ni和Fe中则不存在。 这种差异归因于参考材料的不同超快磁化动力学。 我们的结果支持这样一个假设：平行到反平行的切换需要参考层的快速重新磁化，这会产生一个与自由层磁化方向相反的显著负自旋电流，这是触发其翻转的必要条件。 显示英文摘要

We investigate the magnetization reversal process induced by a single femtosecond laser pulse in ferromagnetic spin valves by systematically comparing reference layers composed of pure Co, Ni, and Fe. To circumvent the loss of perpendicular magnetic anisotropy associated with changes in reference layer material and thickness, we design spin valves with in plane magnetizations. While antiparallel to parallel switching is observed for all three elements, parallel to antiparallel switching occurs only with a Co reference layer and is absent with Ni and Fe. This difference is attributed to the distinct ultrafast magnetization dynamics of the reference materials. Our results support the hypothesis that parallel to antiparallel switching requires a rapid remagnetization of the reference layer, which generates a substantial negative spin current polarized opposite to the free layer magnetization an essential condition for triggering its reversal.

[3] arXiv:2508.21544 [中文pdf, pdf, html, 其他]

标题： 远距离自旋控制在哈德勒纳自旋链中 显示英文标题

标题： Remote spin control in Haldane spin chains

Y. del Castillo, A. Ferrón, J. Fernández-Rossier

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall)

我们考虑使用对另一端的弱局部扰动来远程操控哈德纳自旋链边缘分数自旋的量子态。 我们推导出一个有效的四能级模型，该模型正确地捕捉了局部磁化率对局部扰动的响应，并利用它来证明在链的一端施加一个小的局部场会在链的另一端引起磁化率的强烈变化。 使用一个兰道-泽纳协议，我们展示了如何通过对链一端的场进行局部控制（例如，使用自旋极化的扫描隧道显微镜探针）可以绝热地切换链另一侧的磁化方向。 显示英文摘要

We consider the remote manipulation of the quantum state of the edge fractional spins of Haldane spin chains using a weak local perturbation on the other edge. We derive an effective four-level model that correctly captures the response of the local magnetization to local perturbations and we use it to show that applying a small local field on one edge of the chain induces a strong variation of the magnetization on the opposite edge. Using a Landau-Zener protocol, we show how local control of the field on one edge of the chain, implemented for instance with a spin-polarized scanning tunnel microscope tip, can adiabatically switch the magnetization direction on the other side of the chain.

[4] arXiv:2508.21575 [中文pdf, pdf, 其他]

标题： 带有邻近约瑟夫森结的探针式SQUID显微镜 显示英文标题

标题： Tapping-mode SQUID-on-tip Microscopy with Proximity Josephson Junctions

Matthijs Rog, Tycho J. Blom, Daan B. Boltje, Jimi D. de Haan, Remko Fermin, Jiasen Niu, Yasmin C. Doedes, Milan P. Allan, Kaveh Lahabi

评论： 16页，4图

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 超导性 (cond-mat.supr-con)

研究纳米尺度动力学对于理解量子材料和推动量子芯片制造至关重要。 然而，测量非平衡性质如电流和耗散及其与结构的关系仍然是一个重大挑战。 利用超导量子干涉装置（SQUIDs）的扫描纳米探针在此方面独具优势，因为它们具有无与伦比的磁性和热灵敏度。 在此，我们介绍了敲击模式的SQUID-on-tip，它将原子力显微镜（AFM）与纳米SQUID传感相结合。 我们的探针最小化了纳米SQUID与样品之间的距离，提供了平面内磁灵敏度，并且无需激光操作。 频率复用技术使得能够同时成像电流、磁性、耗散和形貌。 我们接近结纳米SQUID的大电压输出使我们能够使用简单的四探针电子读出系统，在不需要低温放大器的情况下分辨小至100 nA的纳米尺度电流。 通过在不使用外部辐射的情况下捕捉局部磁性、热性和电子响应，我们的技术为研究奇异材料和精细量子电路中的动态现象提供了一种强大的非侵入性方法。 显示英文摘要

Studying nanoscale dynamics is essential for understanding quantum materials and advancing quantum chip manufacturing. Still, it remains a major challenge to measure non-equilibrium properties such as current and dissipation, and their relation to structure. Scanning nanoprobes utilizing superconducting quantum interference devices (SQUIDs) are uniquely suited here, due to their unparalleled magnetic and thermal sensitivity. Here, we introduce tapping-mode SQUID-on-tip, which combines atomic force microscopy (AFM) with nanoSQUID sensing. Our probes minimize nanoSQUID-sample distance, provide in-plane magnetic sensitivity, and operate without lasers. Frequency multiplexing enables simultaneous imaging of currents, magnetism, dissipation and topography. The large voltage output of our proximity-junction nanoSQUIDs allows us to resolve nanoscale currents as small as 100 nA using a simple four-probe electronic readout without cryogenic amplification. By capturing local magnetic, thermal, and electronic response without external radiation, our technique offers a powerful non-invasive route to study dynamic phenomena in exotic materials and delicate quantum circuits.

[5] arXiv:2508.21723 [中文pdf, pdf, html, 其他]

标题： 高保真翻转模式单自旋操作与量子点轨道能级调节 显示英文标题

标题： High fidelity flopping-mode single spin operation with tuning inter-dot orbital levels

Yuta Matsumoto, Xiao-Fei Liu, Arne Ludwig, Andreas D. Wieck, Keisuke Koike, Takefumi Miyoshi, Takafumi Fujita, Akira Oiwa

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 量子物理 (quant-ph)

快速自旋操控和长自旋相干时间是高保真度半导体自旋量子比特的关键特性。然而，通常尚未明确如何同时优化这两个特性，因为这两个特性通常不是相互独立的。因此，一种不依赖于材料相关的强自旋-轨道耦合和限制其可扩展性的局部磁场梯度的高保真操作方案，受到强烈需求。在这里，我们展示了一种通过调节GaAs三量子点（TQD）中的点间自旋-轨道耦合来实现高保真自旋控制的方法，其中第三个量子点提供了对轨道能级的精确控制。在电稳定电荷状态下，通过优化隧穿耦合，我们实现了超过100 MHz的拉比频率，同时通过适当调节TQD的点间轨道能级保持相干性。通过实施基于机器学习的反馈控制，有效地利用过去测量数据估计量子比特频率，我们以最小的测量开销表征并减轻了低频噪声对量子比特相干性的影响。最后，我们通过随机基准测试演示了在GaAs量子点器件中，即使电子自旋相干性通常受核自旋的强超精细相互作用限制，也实现了99.7%的$\pi$/2门保真度，门时间为4 ns。我们的方法通过利用器件特定参数而不是依赖材料特性或外部场梯度，为半导体量子点阵列中的高保真自旋控制提供了一种可扩展的策略。 显示英文摘要

Fast spin manipulation and long spin coherence time in quantum dots are essential features for high fidelity semiconductor spin qubits. However, generally it has not been well established how to optimize these two properties simultaneously, because these two properties are usually not independent from each other. Therefore, the scheme for high fidelity operation by simultaneous tuning Rabi frequency and coherence time, which does not rely on the material-dependent strong spin-orbit interaction and the local magnetic field gradient limiting their scalability, are strongly demanded. Here, we demonstrate an approach to achieve high-fidelity spin control by tuning inter-dot spin-orbit coupling in a GaAs triple quantum dot (TQD), where the third dot provides precise control over orbital energy levels. In an electrically stable charge state with optimized tunnel coupling, we achieve Rabi frequencies exceeding 100 MHz while maintaining coherence through proper tuning of the inter-dot orbital levels of the TQD. By implementing a machine learning-based feedback control that efficiently estimates qubit frequency using past measurement data, we characterize and mitigate the impact of low frequency noise on qubit coherence with minimal measurement overhead. Finally, we demonstrate a $\pi$/2 gate fidelity of 99.7\% with a gate time of 4 ns through randomized benchmarking, even in a GaAs quantum dot device where electron spin coherence is typically limited by strong hyperfine interaction with nuclear spins. Our approach provides a scalable strategy for high-fidelity spin control in semiconductor quantum dot arrays by utilizing device-specific parameters rather than relying on material properties or external field gradients.

[6] arXiv:2508.21743 [中文pdf, pdf, html, 其他]

标题： 拓扑磁振子频率梳 显示英文标题

标题： Topological Magnon Frequency Combs

Zhixiong Li, Xuejuan Liu, Zhejunyu Jin, Guanghua Guo, Xingen Zheng, Peng Yan

评论： 6页，4图

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall)

探索拓扑物理与非线性动力学之间的协同作用，揭示了物质新兴状态的深刻见解。 受光子学中拓扑频梳最近实验演示的启发，我们理论上在二维三角形自旋磁体晶格中引入了拓扑磁振子频梳（MFCs）。 计算磁振子带的陈数揭示了鲁棒的螺旋边缘态。 引人注目的是，这些拓扑MFCs源自螺旋边缘模态之间的非线性四磁振子散射，在双频驱动下无需幅度阈值即可激活。 通过激励频率失谐可轻松调节梳齿间距。 微磁模拟验证了我们的预测，结果高度一致。 这项工作为利用MFCs的无缺陷磁振子器件铺平了道路，并激发了对磁系统中拓扑-非线性现象的研究。 显示英文摘要

Exploring the synergy between topological physics and nonlinear dynamics unveils profound insights into emergent states of matter. Inspired by recent experimental demonstrations of topological frequency combs in photonics, we theoretically introduce topological magnon frequency combs (MFCs) in a two-dimensional triangular skyrmion lattice. Computing the Chern numbers of magnon bands reveals robust chiral edge states. Strikingly, these topological MFCs originate from nonlinear four-magnon scattering among the chiral edge modes, activated by dual-frequency driving without an amplitude threshold. Comb spacings are readily tunable through excitation frequency detuning. Micromagnetic simulations validate our predictions with good concordance. This work paves the way for defect-immune magnonic devices exploiting MFCs and sparks investigations into topological-nonlinear phenomena in magnetic systems.

交叉提交 (展示 13 之 13 条目 )

[7] arXiv:2508.19341 (交叉列表自 quant-ph) [中文pdf, pdf, html, 其他]

标题： 有效双能级系统的最优有限时间热力学 显示英文标题

标题： Optimal Finite-Time Thermodynamics of Effective Two-Level Systems

Alberto Rolandi

评论： 6页，1图，欢迎提出意见

主题： 量子物理 (quant-ph) ; 统计力学 (cond-mat.stat-mech)

热能转化为功的优化以及纳米和介观系统中耗散的最小化是一个复杂的挑战，因为涨落在小系统动力学中起着重要作用。 我们推广了Esposito等人的工作。 EPL 89, 20003 (2010) 以在所有驱动速度下优化从任何有效双态系统中提取最大功所需的控制。 这些系统在对自由度进行粗粒化时出现，这通常是获得“现实世界”双态系统的不可避免步骤。 特别是，只要系统允许通过粗粒化得到马尔可夫主方程，即使系统具有基本的量子动力学，我们也允许这种情况。 我们分析了这些系统的有限时间热力学，并找到了热力学最优协议，这些协议取决于获得双态系统所需的粗粒化大小。 此外，我们利用这些结果推导出对任何有效双态系统执行变换的速度限制。 显示英文摘要

The optimization of the conversion of thermal energy into work and the minimization of dissipation for nano- and mesoscopic systems is a complex challenge because of the important role fluctuations play on the dynamics of small systems. We generalize the work of Esposito et al. EPL 89, 20003 (2010) to optimize at all driving speeds the control needed to extract the maximum amount of work from any effective two-level systems. These emerge when one coarse-grains degrees of freedom, which is often unavoidable to obtain "real-world" two-level systems. In particular, we allow even for the system to have underlying quantum dynamics, as long as these allow for a coarse-graining that leads to a Markovian master equation. We analyze the finite-time thermodynamics of these systems and find the thermodynamically optimal protocols, which depend on the size of the coarse-graining needed to obtain a two-level system. Furthermore, we use these results to derive speed-limits for any transformation performed on an effective two-level system.

[8] arXiv:2508.21117 (交叉列表自 cond-mat.str-el) [中文pdf, pdf, html, 其他]

标题： 电荷密度波诱导的间隙节点线 显示英文标题

标题： Charge density wave induced gapped nodal line

Sergey Alekseev, Lei Chen, Jennifer Cano

评论： 13页，9图

主题： 强关联电子 (cond-mat.str-el) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci)

我们研究了正方形网络材料中电荷密度波（CDW）序与拓扑节点线态之间的相互作用。 我们的吉尔伯特-兰道理论预测了一种CDW不稳定性，通常会在费米能级打开一个间隙，同时保持节点线交叉。 然而，当费米能级接近节点线时，节点线处的态密度会减少，当CDW矢量$\mathbf{Q}$趋近于零时，最终消失。 正好在$\mathbf{Q} = 0$时，序参量明确破坏了保护节点线的滑移对称性，这允许间隙的打开。 然而，对于小但有限的$\mathbf{Q}$，即使滑移对称性被保持，节点线也可能在实验分辨率内消失。 我们的结果为最近的实验观察提供了一个一致的解释。 显示英文摘要

We investigate the interplay between charge density wave (CDW) order and topological nodal-line states in square-net materials. Our Ginzburg-Landau theory predicts a CDW instability that generically opens a gap at the Fermi energy while preserving the nodal line crossing. However, as the Fermi level approaches the nodal line, the density of states at the nodal line decreases, eventually disappearing as the CDW vector $\mathbf{Q}$ goes to zero. Exactly at $\mathbf{Q} = 0$, the order parameter explicitly breaks the glide symmetry protecting the nodal line, which allows a gap to open. Yet, for small but finite $\mathbf{Q}$, the nodal line may vanish within experimental resolution even when the glide symmetry is preserved. Our results provide a consistent explanation for recent experimental observations.

[9] arXiv:2508.21147 (交叉列表自 cond-mat.soft) [中文pdf, pdf, html, 其他]

标题： 凝胶喷射：软微凝胶网络稳定并延长无喷嘴水射流 显示英文标题

标题： Jetting with gels: Soft microgel networks stabilize and extend nozzle-free water jets

Atieh Razavi, Mehrzad Roudini, Andreas Winkler, Benno Liebchen, Regine von Klitzing, Suvendu Mandal, Amin Rahimzadeh

评论： 14页和6图

主题： 软凝聚态物理 (cond-mat.soft) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 化学物理 (physics.chem-ph)

高速液体射流的稳定性对于从精密打印到无针药物输送的应用至关重要，然而它本质上受到毛细管驱动破裂的限制。 稳定射流的一种常见策略是使用表面活性剂来降低表面张力。 然而，在由表面声波（SAWs）驱动的无喷嘴喷射中，极端的变形速率会导致常规表面活性剂脱附，因此需要替代策略来稳定射流。 特别是，我们发现调整PNIPAM微凝胶的纳米尺度柔软度提供了一种强大且生物相容的策略来克服这一限制。 柔软、低交联密度的微凝胶在气-水界面形成弹性界面网络，抑制表面张力恢复，延迟雷利-普拉特勒不稳定性，并将SAW驱动的射流长度延长高达44%。 相比之下，更硬的微凝胶在受力下失去网络凝聚力，导致射流迅速破裂。 为了获得分子级的见解，我们进行了耗散粒子动力学模拟，结果表明，在软微凝胶中，聚合物桥在拉伸过程中保持纠缠，维持较低的有效表面张力。 最后，一种简单的标度分析，平衡了SAW驱动传递给液滴的动能与形成射流所需的表面能，定量预测了观察到的长度增强。 这种无表面活性剂、生物相容的方法为长寿命射流奠定了基础，使无针药物输送、高速打印和其他高应变界面流动应用成为可能。 显示英文摘要

The stability of high-speed liquid jets is crucial for applications ranging from precision printing to needle-free drug delivery, yet it is fundamentally limited by capillary-driven breakup. A common strategy to stabilize jets is to use surfactants to lower surface tension. However, in nozzle-free jetting driven by surface acoustic waves (SAWs), extreme deformation rates cause conventional surfactants to desorb, calling for alternative strategies to stabilize jets. In particular, we find that tuning the nanoscale softness of PNIPAM microgels provides a robust, biocompatible strategy to overcome this limitation. Soft, low-cross-linker-density microgels form elastic interfacial networks at the air-water interface that suppress surface tension recovery, delay Rayleigh-Plateau instabilities, and extend SAW-driven jet lengths by up to 44%. In contrast, stiffer microgels lose network cohesion under strain, leading to rapid jet breakup. To gain molecular-level insights, we perform dissipative particle dynamics simulations, which reveal that polymer bridges in soft microgels remain entangled during elongation, maintaining a reduced effective surface tension. Finally, a simple scaling analysis, balancing the SAW-driven kinetic energy imparted to the droplet against the surface energy required to form a jet, quantitatively predicts the observed length enhancement. This surfactant-free, biocompatible approach lays the foundation for long-lived jets, enabling precision needle-free drug delivery, high-speed printing, and other high-strain interfacial flow applications.

[10] arXiv:2508.21200 (交叉列表自 quant-ph) [中文pdf, pdf, html, 其他]

标题： LREI：量子兰道-利夫希茨方程的快速数值求解器 显示英文标题

标题： LREI: A fast numerical solver for quantum Landau-Lifshitz equations

Davoud Mirzaei, Behnam Hashemi, Vahid Azimi-Mousolou

评论： 23页和12图

主题： 量子物理 (quant-ph) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 数值分析 (math.NA) ; 计算物理 (physics.comp-ph)

我们开发了LREI（低秩本征模积分），这是一种用于求解量子兰道-利夫希茨（q-LL）和量子兰道-利夫希茨-吉尔伯特（q-LLG）方程的内存和时间高效的方案，这些方程描述开放量子系统中的自旋动力学。虽然系统尺寸随着自旋数量呈指数增长，但我们的方法利用密度矩阵的低秩结构和哈密顿量的稀疏性来避免完整的矩阵计算。通过使用低秩因子表示密度矩阵，并应用Krylov子空间方法进行部分特征分解，我们将龙格-库塔和亚当斯-巴什福思方案的每步复杂度从$\mathcal{O}(N^3)$降低到$\mathcal{O}(r^2N)$，其中$N = 2^n$是$n$个自旋的希尔伯特空间维度，$r \ll N$是有效秩。 类似地，内存成本从$\mathcal{O}(N^2)$减少到$\mathcal{O}(rN)$，因为没有形成完整的$N\times N$矩阵。一个关键的进展是处理零特征值的不变子空间。通过使用为主要特征空间构建的豪斯霍尔德反射，我们完全避免了大矩阵的使用。例如，一个二十自旋系统的时步，其密度矩阵大小超过一百万，现在在标准笔记本电脑上仅需几秒钟。龙格-库塔方法和阿达姆斯-巴什福思方法都被重新表述，以在整个演化过程中保持密度矩阵的物理特性。这种低秩算法使得对更大自旋系统的模拟成为可能，这些系统之前是不可行的，为比较 q-LL 和 q-LLG 动力学提供了强大的工具，测试每个模型的有效性，并探究量子特性如关联和纠缠如何在不同系统尺寸和阻尼区域中演化。 显示英文摘要

We develop LREI (Low-Rank Eigenmode Integration), a memory- and time-efficient scheme for solving quantum Landau-Lifshitz (q-LL) and quantum Landau-Lifshitz-Gilbert (q-LLG) equations, which govern spin dynamics in open quantum systems. Although system size grows exponentially with the number of spins, our approach exploits the low-rank structure of the density matrix and the sparsity of Hamiltonians to avoid full matrix computations. By representing density matrices via low-rank factors and applying Krylov subspace methods for partial eigendecompositions, we reduce the per-step complexity of Runge-Kutta and Adams-Bashforth schemes from $\mathcal{O}(N^3)$ to $\mathcal{O}(r^2N)$, where $N = 2^n$ is the Hilbert space dimension for $n$ spins and $r \ll N$ the effective rank. Similarly, memory costs shrink from $\mathcal{O}(N^2)$ to $\mathcal{O}(rN)$, since no full $N\times N$ matrices are formed. A key advance is handling the invariant subspace of zero eigenvalues. By using Householder reflectors built for the dominant eigenspace, we perform the solution entirely without large matrices. For example, a time step of a twenty-spin system, with density matrix size over one million, now takes only seconds on a standard laptop. Both Runge-Kutta and Adams-Bashforth methods are reformulated to preserve physical properties of the density matrix throughout evolution. This low-rank algorithm enables simulations of much larger spin systems, which were previously infeasible, providing a powerful tool for comparing q-LL and q-LLG dynamics, testing each model validity, and probing how quantum features such as correlations and entanglement evolve across different regimes of system size and damping.

[11] arXiv:2508.21247 (交叉列表自 physics.optics) [中文pdf, pdf, html, 其他]

标题： 明亮而黑暗：强耦合如何抑制激子-极化子辐射 显示英文标题

标题： Bright yet dark: how strong coupling quenches exciton-polariton radiation

Jiaxun Song, Li He, Bo Zhen

主题： 光学 (physics.optics) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

理解激子极化子的辐射衰减对于实现长寿命极化子至关重要——这是增强非线性和量子极化子效应的关键前提。 然而，传统观点——耦合振子模型——通常将极化子辐射简化为未耦合的激子和光子共振的独立发射，忽视了强激子-光子耦合在重塑其辐射行为中的作用。 在本工作中，我们提出了一种理论框架，通过充分考虑激子-光子相互作用的集体和相干特性，超越了传统的耦合振子模型。 我们证明，这些相互作用可以通过破坏性干涉强烈抑制极化子辐射——既在激子集合内部，又在激子和光子辐射通道之间——从而产生具有无限长辐射寿命的极化子连续谱束缚态。 我们的方法提供了一个统一的极化子辐射衰减描述，并建立了设计具有定制辐射特性的长寿命激子极化子的新原则，为非线性、拓扑和量子极化子应用开辟了新途径。 显示英文摘要

Understanding the radiative decay of exciton-polaritons is essential for achieving long-lived polaritons - a key prerequisite for enhancing nonlinear and quantum polaritonic effects. However, conventional wisdom - the coupled oscillator model - often oversimplifies polariton radiation as independent emissions from uncoupled excitonic and photonic resonances, overlooking the role of strong exciton-photon coupling in reshaping their radiative behavior. In this work, we present a theoretical framework that goes beyond the conventional coupled oscillator model by fully accounting for the collective and coherent nature of exciton-photon interactions. We demonstrate that these interactions can strongly suppress polariton radiation via destructive interference - both within the excitonic ensemble and between excitonic and photonic radiation channels - giving rise to polaritonic bound states in the continuum with infinitely long radiative lifetimes. Our approach offers a unified description of polariton radiative decay and establishes new design principles for engineering long-lived exciton-polaritons with tailored radiation properties, opening new avenues for nonlinear, topological, and quantum polaritonic applications.

[12] arXiv:2508.21326 (交叉列表自 cond-mat.str-el) [中文pdf, pdf, html, 其他]

标题： 磁化螺旋边缘态与s波超导体的电子关联 显示英文标题

标题： Electronic correlations in magnetized helical edge states coupled to s-wave superconductors

Zeinab Bakhshipour, Mir Vahid Hosseini

评论： 18页，9图

主题： 强关联电子 (cond-mat.str-el) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 超导性 (cond-mat.supr-con)

我们理论研究了电子-电子相互作用在耦合到s波超导体的一维磁化螺旋态中的作用。 我们考虑了一个部分混合的螺旋（超螺旋）区域，其中磁场（超导性）具有主导贡献。 使用玻色化和重整化群技术，展示了相互作用如何影响系统中的关联函数。 在部分混合的螺旋区域，我们发现超导配对促进了自旋密度波关联，而单态和三重态配对关联则被抑制，尤其是在吸引相互作用下。 相反，在超螺旋区域，微扰的Zeeman场在排斥相互作用下增强了自旋单态和自旋三重态-x配对。 我们计算了电荷密度波、自旋密度波和配对关联的对数和残留修正，揭示了短程和长程行为。 我们进一步研究了自旋输运特性，并通过重整化群分析了自旋电导率的温度和频率依赖性。 我们还分析了在Zeeman诱导和配对诱导能隙存在下的动量-自旋锁定载流子的输运，揭示了相互作用的影响以及两个能隙在螺旋系统中的相互作用。 显示英文摘要

We theoretically study the role of electron-electron interactions in one-dimensional magnetized helical states coupled to an s-wave superconductor. We consider a partially mixed helical (superhelical) regime, where the magnetic field (superconductivity) has a dominant contribution. Using bosonization and renormalization group techniques, it is shown how the interactions affect the correlation functions in the system. In the partially mixed helical regime, we find that superconducting pairing promotes spin-density-wave correlations, while singlet and triplet pairing correlations suppress, especially under attractive interactions. In contrast, in the superhelical regime, a perturbative Zeeman field enhances both spin singlet and spin triplet-x pairings under repulsive interactions. We calculate both logarithmic and residual corrections to charge-density-wave, spin-density-wave, and pairing correlations, revealing short- and long-range behaviors. We further investigate spin transport properties supplemented by a renormalization group analysis of the temperature and frequency dependence of spin conductivity. We also analyze the transport of momentum-spin-locked carriers in the presence of Zeeman-induced and pairing-induced gaps, uncovering the effect of interactions and the interplay between the two gaps in helical systems.

[13] arXiv:2508.21359 (交叉列表自 cond-mat.mtrl-sci) [中文pdf, pdf, 其他]

标题： 可调谐的二维电子气在铁电钽酸钾铌酸盐的界面处 显示英文标题

标题： Tunable Two-Dimensional Electron Gas at the Interfaces of Ferroelectric Potassium Tantalate Niobates

Jiaxin Lv, Silan Li, Chenhao Duan, Shuanhu Wang, Hong Yan, Kexin Jin

主题： 材料科学 (cond-mat.mtrl-sci) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

复杂氧化物的异质界面已成为发现新物理现象和推动集成传感、存储和计算技术发展的有前途的平台。 然而，在铁电氧化物基场效应晶体管（FET）结构中实现对二维电子气（2DEG）的精确控制仍然具有挑战性。 在此，我们首次展示了通过在(001)取向的铁电钽酸钾铌基板上沉积非晶态LaAlO3（LAO）薄膜而制成的可调谐2DEG系统。 在高温和高氧压条件下生长的界面表现出良好的金属导电性。 值得注意的是，在108 K以下观察到了具有明显迟滞效应和持续电场调制电阻的明确金属2DEG，在7 K时实现了11.6%的电阻调制。这些结果强调了将这种行为扩展到其他氧化物基2DEG系统的潜力，并有助于进一步探索复杂氧化物异质结构中的铁电金属。 显示英文摘要

The heterointerfaces at complex oxides have emerged as a promising platform for discovering novel physical phenomena and advancing integrated sensing, storage, and computing technologies. Nevertheless, achieving precise control over a two-dimensional electron gas (2DEG) in a ferroelectric oxide-based field-effect transistor (FET) configuration remains challenging. Here, we firstly demonstrate a tunable 2DEG system fabricated by depositing an amorphous LaAlO3(LAO) film onto a (001)-oriented ferroelectric potassium tantalate niobate substrate. Interfaces grown under high-temperature and high-oxygen-pressure conditions exhibit a good metallic conduction. Notably, well-defined metallic 2DEGs displaying pronounced hysteresis and persistent electric-field-modulated resistance are observed below 108 K, achieving a resistance modulation of 11.6% at 7 K. These results underscore the potential for extending such behavior to other oxide-based 2DEG systems and facilitate further exploration of ferroelectric metals in complex oxide heterostructures.

[14] arXiv:2508.21425 (交叉列表自 physics.app-ph) [中文pdf, pdf, 其他]

标题： 当能源与信息革命相遇 2D Janus 显示英文标题

标题： When Energy and Information Revolutions Meet 2D Janus

Long Zhang, Ziqi Ren, Li Sun, Yihua Gao, Deli Wang, Junjie He, Guoying Gao

评论： 114页，21幅图和7张表

主题： 应用物理 (physics.app-ph) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 化学物理 (physics.chem-ph) ; 计算物理 (physics.comp-ph)

能源资源的枯竭、环境问题的恶化以及后摩尔时代集成电路在信息存储中的量子限制，是紧迫的全球性问题。 幸运的是，二维（2D）Janus材料，具有破坏的空间对称性，具有新兴的压力依赖性和非线性光学响应、压电性、谷极化、Rashba自旋分裂等特性，已在材料科学中建立了探索和应用可调节物理、化学和生物特性的坚实平台，并为这些能源和信息问题提供了一个有前景的解决方案。 为了向研究人员提供一个全面的2D Janus家族资料库，本综述系统地总结了它们的理论预测、实验制备和调制策略。 它还回顾性地概述了光学、催化、压电性、电化学、热电性、磁性和电子学中可调节特性、应用和内在机制的最新进展，重点介绍了实验实现的六边形和三角形Janus结构。 此外，还总结了它们当前的研究状态，并强调了可能遇到的潜在机遇和挑战。 总体而言，本综述旨在作为设计、制造、调控和应用2D Janus系统的宝贵资源，无论是理论还是实验方面。 本综述将大力促进2D Janus材料在能源和信息领域先进的学术研究和工业应用。 显示英文摘要

The depletion of energy sources, worsening environmental issues, and the quantum limitations of integrated circuits for information storage in the post-Moore era, are pressing global concerns. Fortunately, two-dimensional (2D) Janus materials, possessing broken spatial symmetry, with emerging pressure-dependent and non-linear optical response, piezoelectricity, valley polarization, Rashba spin splitting and more, have established a substantial platform for exploring and applying modifiable physical, chemical and biological properties in material science and offered a promising solution for these energy and information issues. To furnish researchers with a comprehensive repository of 2D Janus family, this review systematically summarizes their theoretical predictions, experimental preparations, and modulation strategies. It also retrospectively outlines the recent advances in modifiable properties, applications, and inherent mechanisms in optics, catalysis, piezoelectricity, electrochemistry, thermoelectricity, magnetism, and electronics, with a focus on experimentally realized hexagonal and trigonal Janus structures. Additionally, their current research state is summarized, and potential opportunities and challenges that may arise are highlighted. Overall, this review aims to serve as a valuable resource for designing, fabricating, regulating, and applying 2D Janus systems, both theoretically and experimentally. This review will strongly promote the advanced academic investigations and industrial applications of 2D Janus materials in energy and information fields.

[15] arXiv:2508.21464 (交叉列表自 math.AP) [中文pdf, pdf, 其他]

标题： 1D准解的2D Chern-Simons-Schr{ö}方程组 显示英文标题

标题： 1D quasi-solutions of the 2D Chern-Simons-Schr{ö}dinger system

Nicolas Rougerie (UMPA-ENSL), Qiyun Yang (UMPA-ENSL)

主题： 偏微分方程分析 (math.AP) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 量子气体 (cond-mat.quant-gas) ; 数学物理 (math-ph)

我们研究一个二维阿贝尔任意子系统的平均场模型，该模型由薛定谔物质场与陈-西蒙斯规范场的动态耦合给出。 我们通过添加一个强各向异性的捕获势（波导）作用于薛定谔场，并对紧密约束方向进行积分，推导出一个有效的1D方程。 波导松散方向的有效动力学被证明由经典的1D五次NLS方程支配。 显示英文摘要

We study a mean-field model for a system of 2D abelian anyons, given by the dynamics of a Schr{\"o}dinger matter field coupled to a Chern-Simons gauge field. We derive an effective 1D equation by adding a strongly anisotropic trapping potential (wave-guide) acting on the Schr{\"o}dinger field, and tracing out the tight confinement direction. The effective dynamics in the loose direction of the wave-guide turns out to be governed by the classical 1D quintic NLS equation.

[16] arXiv:2508.21492 (交叉列表自 cond-mat.mtrl-sci) [中文pdf, pdf, 其他]

标题： 通过调节基底与金属的相互作用控制沉积的面心立方金属的生长形态 显示英文标题

标题： Control of growth morphology of deposited fcc metals through tuning substrate-metal interactions

Samuel Aldana, Michael Nolan

评论： 58页，10图

主题： 材料科学 (cond-mat.mtrl-sci) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 计算物理 (physics.comp-ph)

精确控制薄膜形貌对于优化各种技术应用中的材料性能至关重要，因为生长模式（无论是二维逐层还是三维岛状形成）决定了关键的功能特性，例如在CMOS互连应用中的电导率和催化活性，在这些情况下，岛的分布和尺寸决定了性能。 为了探索基底对沉积金属形貌的作用，我们对六种面心立方金属在(111)方向上的生长进行了广泛的蒙特卡罗动力学模拟：Ag、Au、Cu、Ni、Pd和Pt。 我们的模拟框架能够在同质外延生长情景下筛选和评估它们的生长模式，并通过改变基底-金属相互作用强度提出形貌控制策略，该强度通过修改向上和向下迁移的活化能来建模，并结合典型的后端工艺（BEOL）集成热预算内的热真空退火。 我们的模拟结果表明，调节基底相互作用强度可以有效地用于促进岛状形成或逐层生长模式，克服在实现大面积平坦表面方面的限制。 Au、Pd和Pt对基底相互作用强度的变化最敏感，其次是Ag，这表明强相互作用的基底会降低均方根（RMS）粗糙度、未覆盖基底暴露、岛的数量和岛的纵横比，同时适度增加平坦表面面积和原子配位数。 此外，通过热真空退火改善了互连相关指标，特别是当使用足够强的金属-基底相互作用时，可减少表面粗糙度，实现更大的平坦表面面积，合并和平滑岛，并减少缺陷密度。 显示英文摘要

Precise control over thin film morphology is critical for optimizing material properties across diverse technological applications, as the growth mode (whether 2D layer-by-layer or 3D island formation)determines key functional properties such as electrical conductivity in CMOS interconnect applications and catalytic activity, where island distribution and size dictate performance. To explore the role of the substrate on the morphology of deposited metals, we present extensive kinetic Monte Carlo simulations on six fcc metals growing in the (111) direction: Ag, Au, Cu, Ni, Pd and Pt. Our simulation framework enables screening and evaluation of their growth mode under homoepitaxial growth scenarios and proposes morphology control strategies by variation of substrate-metal interaction strengths, modeled by modifying the activation energies for upward and downward migration, combined with thermal vacuum annealing within typical back end of line (BEOL) integration thermal budget. Our simulation results demonstrate that modulation of the substrate interaction strength can be effectively employed to promote island formation or layer-by-layer growth modes overcoming limitations in achieving large flat surface areas. Au, Pd and Pt exhibit the highest sensitivity to substrate interaction strength variations, followed by Ag, showing that strongly interacting substrates decrease the root mean square (RMS) roughness, (uncovered) substrate exposure, island number and island aspect ratios, with moderate increases in flat surface areas and atomic coordination numbers. Additionally, interconnect relevant metrics are improved through thermal vacuum annealing particularly when sufficiently strong metal-substrate interactions are employed, reducing surface roughness, achieving larger flat surface areas, merging and smoothing islands, and decreasing defect density...

[17] arXiv:2508.21526 (交叉列表自 cond-mat.mtrl-sci) [中文pdf, pdf, html, 其他]

标题： 基于萘的二维 MoS$_2$-有机杂化材料中机械各向异性和能带对齐的化学控制 显示英文标题

标题： Chemical Control of Mechanical Anisotropy and Band Alignment in Perylene-based Two-dimensional MoS$_2$-Organic Hybrids

Mohammed El Amine Miloudi, Oliver Kühn

主题： 材料科学 (cond-mat.mtrl-sci) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

本研究对由单层MoS$_2$与有机分子苝（P）、苝二酰亚胺（PDI）和苝橙（PO）形成的混合界面进行了全面的研究。 使用密度泛函理论，我们展示了通过给定发色团的化学修饰，混合系统在机械和电子性能方面可以被改变的程度。 由于它们的化学组成和几何结构所允许的范德华接触，这三个系统表现出显著的差异。 所有系统在结构上都是稳定的。 结合能的顺序为 PD$>$P$>$PO，这是由于较大的$\pi$-系统（PD）和强烈的结构畸变 （PO）。 杨氏模量和泊松比在所有情况下都表现出明显的各向异性。 PO由于立体效应和永久偶极子而表现出最大的各向异性，这些因素使分子-表面相互作用具有方向性。 物理吸附伴随着净电荷转移，其顺序与结合能相同。 相关的界面极化导致功函数的变化，顺序为 P$>$PO$>$PD 相对于原始的MoS$_2$。 最后，有机分子的存在将状态引入到MoS$_2$能量间隙中，带对齐方式为II型(P, PO)或I型(PD)。 显示英文摘要

This study presents a comprehensive investigation of hybrid interfaces formed by monolayer MoS$_2$ coupled with the organic molecules perylene (P), perylene diimide (PDI), and perylene orange (PO). Using density functional theory, we demonstrate the extent to which the mechanical and electronic properties of a hybrid system can be altered by the chemical modification of a given chromophore. The three systems exhibit distinct differences due to their chemical composition and van der Waals contact enabled by their geometry. All systems are structurally stable. The binding energies follow the order PD$>$P$>$PO due to the large $\pi$-system (PD) and strong structural distortion (PO). Young's modulus and Poisson's ratio exhibit pronounced anisotropy in all cases. PO exhibits the greatest anisotropy due to steric effects and a permanent dipole, which introduce directionality to the molecule-surface interaction. Physisorption is accompanied by net charge transfer in the same order as the binding energies. The associated interfacial polarization results in a change in the work function compared to pristine MoS$_2$ in the order P$>$PO$>$PD. Finally, the presence of organic molecules introduces states into the MoS$_2$ energy gap, with the band alignment being either type II (P, PO) or type I (PD).

[18] arXiv:2508.21700 (交叉列表自 physics.optics) [中文pdf, pdf, html, 其他]

标题： 光子平坦带晶格中NOON态动力学的实验构建 显示英文标题

标题： Experimental Construction of NOON State Dynamics in Photonic Flat Band Lattices

Rishav Hui, Trideb Shit, Marco Di Liberto, Diptiman Sen, Sebabrata Mukherjee

评论： 欢迎提出评论

主题： 光学 (physics.optics) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 量子物理 (quant-ph)

我们研究了路径纠缠多光子NOON态在平坦带光子菱形晶格中的传输，并观察到与NOON态的相位以及光子数相关的有趣局域化-非局域化特性。 为了实验模拟光子数相关性，我们开发了一种使用可调相对相位的相干激光光进行强度相关性测量的协议。 我们首先应用此协议来展示由相同波导组成的一维晶格中双光子NOON态的空间聚集和反聚集现象。 在菱形晶格的情况下，我们表明对于偶数（奇数）光子数$N$，在NOON态的$0 \, (\pi)$相位上会发生局域化，概率为$2^{1-N}$。 我们的结果为预测复杂光子网络中关联光子的量子干涉提供了一条令人兴奋的途径。 显示英文摘要

We investigate the transport of path-entangled multi-photon NOON states in a flat-band photonic rhombic lattice and observe intriguing localization-delocalization features that depend on the phase as well as the photon number of the NOON states. To experimentally emulate photon number correlations, we develop an intensity correlation measurement protocol using coherent laser light with tunable relative phases. We first apply this protocol to show spatial bunching and anti-bunching of two-photon NOON states in a one-dimensional lattice consisting of identical waveguides. In the case of the rhombic lattice, we show that for an even (odd) photon number $N$, localization occurs at $0 \, (\pi)$ phase of the NOON state with a probability of $2^{1-N}$. Our results open an exciting route toward predicting quantum interference of correlated photons in complex photonic networks.

[19] arXiv:2508.21791 (交叉列表自 cond-mat.supr-con) [中文pdf, pdf, html, 其他]

标题： 量子几何诱导的哈德纳相中的凯库勒超导性 显示英文标题

标题： Quantum Geometry Induced Kekulé Superconductivity in Haldane phases

Yafis Barlas, Fan Zhang, Enrico Rossi

评论： 8页

主题： 超导性 (cond-mat.supr-con) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

手性二维电子气体，捕捉了石墨烯和菱形石墨烯系统的电子特性，表现出奇异的动量空间涡旋，并容易受到相互作用引起的拓扑哈德纳相的影响。 在这里，我们研究手性二维电子气体的反演对称哈德纳相中的配对相互作用。 我们证明哈德纳相的非平凡带拓扑相对于谷间（${\bf Q} = 0$）配对倾向，增强了谷内（${\bf Q} = \pm 2 {\bf K_D}$）配对倾向，促进了晶格尺度的配对密度波序的出现。 当纵向声学声子介导配对相互作用时，系统支持手性凯库勒超导序。 我们的发现与菱形石墨烯和凯格米金属中的超导性有关。 显示英文摘要

Chiral two-dimensional electron gases, which capture the electronic properties of graphene and rhombohedral graphene systems, exhibit singular momentum-space vortices and are susceptible to interaction-induced topological Haldane phases. Here, we investigate pairing interactions in these inversion-symmetric Haldane phases of chiral two-dimensional electron gases. We demonstrate that the nontrivial band topology of the Haldane phases enhances intra-valley (${\bf Q} = \pm 2 {\bf K_D}$) pair susceptibility relative to inter-valley (${\bf Q} = 0$) pair susceptibility, favoring the emergence of a lattice-scale pair-density wave order. When longitudinal acoustic phonons mediate the pairing interaction, the system supports a chiral Kekul\`{e} superconducting order. Our findings are relevant to superconductivity in rhombohedral graphene and Kagome metals.

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[20] arXiv:2304.04825 (替换) [中文pdf, pdf, html, 其他]

标题： 倒置不对称性对双层石墨烯超导和激子凝聚的影响 显示英文标题

标题： Effect of Inversion Asymmetry on Bilayer Graphene's Superconducting and Exciton Condensates

Xiang Hu, Enrico Rossi, Yafis Barlas

评论： 更新版本

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 超导性 (cond-mat.supr-con)

双层石墨烯中的反演不对称性可以通过位移场进行调节。 因此，偏置双层石墨烯中的能带色散在狄拉克点附近呈现出平带区域，并伴随非平凡的能带几何结构。 我们分析了反演对AB堆叠石墨烯双层超导态临界温度和超流刚度以及由两个AB堆叠石墨烯双层形成的双层中激子凝聚的影响。 发现双层石墨烯超导体中的几何超流刚度由于超导能隙较小而可以忽略不计。 此外，我们表明几何超流刚度在常数序参量下达到最大值。 因此，在具有任何配对对称性的偏置双层石墨烯超导体中可以忽略不计。 然而，位移场增强了激子凝聚中的几何超流刚度。 在低密度和高位移场时最为显著。 几何超流刚度的一个结果是双层石墨烯激子凝聚中的贝瑞辛斯基-科斯特里茨-索利斯转变温度适度提高。 显示英文摘要

Inversion asymmetry in bilayer graphene can be tuned by the displacement field. As a result, the band dispersion in biased bilayer graphene acquires flat band regions near the Dirac points along with a non-trivial band geometry. We analyze the effect of inversion symmetry on the critical temperature and superfluid stiffness of the superconducting state of AB-stacked graphene bilayer and on the exciton condensate in double layers formed by two AB-stacked graphene bilayers. The geometric superfluid stiffness in bilayer graphene superconductors is found to be negligible due to the small superconducting gap. Furthermore, we show that the geometric superfluid stiffness is maximized for a constant order parameter. Therefore, it can be neglected in biased bilayer graphene superconductors with any pairing symmetry. However, the displacement field enhances the geometric superfluid stiffness in exciton condensates. It is most prominent at low densities and high displacement fields. A consequence of the geometric superfluid stiffness is a modest enhancement of the Berezinskii-Kosterlitz-Thouless transition temperature in bilayer graphene's exciton condensate.

[21] arXiv:2407.01277 (替换) [中文pdf, pdf, html, 其他]

标题： 电流在量子霍尔效应区域的性质 显示英文标题

标题： Nature of current flow in the regime of the quantum Hall effect

Serkan Sirt, Matthias Kamm, Vladimir Y. Umansky, Stefan Ludwig

评论： 14页，13图

期刊参考： 新物理学杂志 27 083507 (2025)

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall)

整数量子霍尔效应（QHE）是固体物理中最基本的现象之一，并作为电阻标准有重要的应用。 它是理解分数量子霍尔效应、反常量子霍尔效应或自旋量子霍尔效应的基础，由于其拓扑性质，它们是量子技术的候选材料。 为了优化所有这些应用，理解霍尔条中的电流流动位置是至关重要的，这个问题已经争论了几十年。 我们在霍尔条上进行多端电流测量，并将结果与极限模型进行比较。 我们根据这些实验确认，在量化霍尔电阻平台处，电流流动是手性的。 在其他任何地方，包括平台之间的区域，我们的结果符合德鲁德模型，该模型预测均匀霍尔条中的电流流动是均匀的。 显示英文摘要

The integer quantum Hall effect (QHE) belongs to the most fundamental phenomena of solid state physics and has an important application as resistance standard. It serves as a basis to understand the fractional, anomalous or spin QHEs, candidates for applications in quantum technology due to their topological properties. For optimizing all these applications it is essential to understand where the current flows inside the Hall bar, a question disputed for decades. We perform multiterminal current measurements on a Hall bar and compare the results with limiting models. We confirm, based on these experiments, that the current flow is chiral for the plateaus of quantized Hall resistance. Everywhere else, including the ranges between plateaus, our results comply with the Drude model, which predicts homogeneous current flow across a homogeneous Hall-bar.

[22] arXiv:2411.06058 (替换) [中文pdf, pdf, html, 其他]

标题： 提出的五电子电荷四极子量子比特 显示英文标题

标题： Proposed Five-Electron Charge Quadrupole Qubit

John H. Caporaletti, J. P. Kestner

评论： 6页，3图，补充材料

期刊参考： 物理评论快报 135, 070803 (2025)

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 量子物理 (quant-ph)

一个电荷量子比特通过其偶极矩与环境电场涨落耦合，导致快速退相干。 我们提出了p轨道(pO)量子比特，它由五个电子的硅量子点的单个电子、类似p的价态形成，通过四极矩与电荷噪声耦合。 我们证明pO量子比特在品质因数、门速度、读出和尺寸方面具有显著优势。 我们使用一种经验性的偶极子两能级涨落电荷噪声模型来估计一个$T_2^* \sim 80$ ns。 结合约10 GHz的拉比频率，相对于最先进的半导体自旋量子比特，量子比特的品质因数有望提高一个数量级。 pO量子比特通过调节量子点的偏心率实现全电气控制。 我们还展示了如何通过$1/r^5$四极矩-四极矩相互作用执行双量子比特门。 我们在最大允许带宽为10 GHz和脉冲时间为1 ns的条件下，使用基于梯度上升的控制脉冲优化方法找到一个通用门集。 显示英文摘要

A charge qubit couples to environmental electric field fluctuations through its dipole moment, resulting in fast decoherence. We propose the p orbital (pO) qubit, formed by the single electron, p-like valence states of a five-electron Si quantum dot, which couples to charge noise through the quadrupole moment. We demonstrate that the pO qubit offers distinct advantages in quality factor, gate speed, readout and size. We use a phenomenological, dipole two-level-fluctuator charge noise model to estimate a $T_2^* \sim 80$ ns. In conjunction with Rabi frequencies of order 10 GHz, an order of magnitude improvement in qubit quality factor is expected relative to state-of-the-art semiconductor spin qubits. The pO qubit features all-electrical control via modulating the dot's eccentricity. We also show how to perform two-qubit gates via the $1/r^5$ quadrupole-quadrupole interaction. We find a universal gate set using gradient ascent based control pulse optimization, subject to 10 GHz maximum allowable bandwidth and 1 ns pulse times.

[23] arXiv:2502.18236 (替换) [中文pdf, pdf, html, 其他]

标题： 声子热霍尔效应作为晶格阿哈罗诺夫-博姆效应 显示英文标题

标题： Phonon thermal Hall as a lattice Aharonov-Bohm effect

Kamran Behnia

评论： 23页，6图，2表

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 量子气体 (cond-mat.quant-gas) ; 量子物理 (quant-ph)

在越来越多的绝缘体中，实验发现磁场会在热通量矢量和温度梯度矢量之间引起不对齐现象。 这种现象被称为声子热霍尔效应，意味着在垂直于温度梯度的方向上存在能量流动而没有熵的产生。 在各种绝缘体中测得的热霍尔角度不超过一个上限，并在纵向热导率峰值温度时达到最大值。 本文旨在提出一种情景，以解释这两个实验事实。 它首先注意到，在这个温度下，$T_{max}$，正常声子-声子碰撞比倒格散射和边界散射事件更为频繁。 此外，已知在磁场存在下，Born-Oppenheimer近似分子波函数会获得一个相位。 在一个非谐晶体中，拉伸和压缩应变不会相互抵消，这种场诱导的原子相位会导致声子贝里相位并产生声子-声子干涉。 在这个图景中预期的热霍尔角度的粗略幅度由声子波长，$\lambda_{ph}$和在$T_{max}$处的峰原子位移，$\delta u_m$确定。 推导出的表达式与在黑磷、锗和硅中实验发现的结果惊人地接近。 显示英文摘要

In a growing list of insulators, experiments find that magnetic field induces a misalignment between the heat flux and the thermal gradient vectors. This phenomenon, known as the phonon thermal Hall effect, implies energy flow without entropy production along the orientation perpendicular to the temperature gradient. The experimentally-measured thermal Hall angle in various insulators does not exceed a bound and becomes maximal at the temperature of peak longitudinal thermal conductivity. The present paper aims to propose a scenario providing and explanation for these two experimental facts. It begins by noticing that at this temperature, $T_{max}$, Normal phonon-phonon collisions become most frequent in comparison with Umklapp and boundary scattering events. Furthermore, the Born-Oppenheimer approximated molecular wave functions are known to acquire a phase in the presence of a magnetic field. In an anharmonic crystal, in which tensile and compressive strain do not cancel out, this field-induced atomic phase gives rise to a phonon Berry phase and generates phonon-phonon interference. The rough amplitude of the thermal Hall angle expected in this picture is set by the phonon wavelength, $\lambda_{ph}$, and the crest atomic displacement, $\delta u_m$ at $T_{max}$. The derived expression is surprisingly close to what has been experimentally found in black phosphorus, germanium and silicon.

[24] arXiv:2503.20486 (替换) [中文pdf, pdf, html, 其他]

标题： 特征行列式方法在求解一维$\mathcal{P}\mathcal{T}$对称系统谱中的应用 显示英文标题

标题： Characteristic determinant approach to the spectrum of one-dimensional $\mathcal{P}\mathcal{T}$-symmetric systems

Vladimir Gasparian, Peng Guo, Antonio Pérez Garrido, Esther Jódar

评论： 标题更改为“一维$\mathcal{P}\mathcal{T}$对称系统的谱的特征行列式方法”。文本中的一些小改动以匹配PRR接受版本

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 其他凝聚态物理 (cond-mat.other)

我们得到了具有周期性两个$\delta$势的单元中复势的$\mathcal{P}\mathcal{T}$对称超晶格系统的能量谱的闭合形式表达式。 在存在周期性增益和损耗的情况下，我们详细分析了一个双原子晶体模型，改变散射体距离或势的高度。 结果表明，在复振幅的虚部的某个临界值下，依赖于晶格尺寸和单元结构的拓扑态可能会消失。 这可能发生在$\mathcal{PT}$对称性破缺（异常）点。 显示英文摘要

We obtain a closed form expression for the energy spectrum of $\mathcal{P}\mathcal{T}$-symmetric superlattice systems with complex potentials of periodic sets of two $\delta$-potentials in the elementary cell. In the presence of periodic gain and loss we analyzed in detail a diatomic crystal model, varying either the scatterer distances or the potential heights. It is shown that at a certain critical value of the imaginary part of the complex amplitude, topological states depending on the lattice size and the configuration of the unit cell can disappear. This may happened at the $\mathcal{PT}$-symmetry breaking (exceptional) points.

[25] arXiv:2504.02037 (替换) [中文pdf, pdf, html, 其他]

标题： 二维富勒烯网络中的负和正各向异性热膨胀 显示英文标题

标题： Negative and positive anisotropic thermal expansion in 2D fullerene networks

Armaan Shaikh, Jiaqi Wu, Bo Peng

评论： 8页，5图

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 原子与分子簇 (physics.atm-clus) ; 化学物理 (physics.chem-ph) ; 计算物理 (physics.comp-ph)

我们发现了一种设计原则，用于调节近球形分子网络的热膨胀特性。 使用二维富勒烯网络作为代表性系统，我们通过改变分子的结构框架，在分子间[2 + 2]环加成键上实现了正热膨胀，在分子间C$-$C单键上实现了负热膨胀。 微观机制源于框架几何柔性和横向振动特性的结合。 基于这一见解，我们发现了超越C$_{60}$的可调热膨胀分子网络。 这些发现为理解分子网络中热膨胀的基本机制提供了启示，有助于合理材料的设计。 显示英文摘要

We find a design principle for tailoring thermal expansion properties in nearly-spherical molecular networks. Using 2D fullerene networks as a representative system, we realize positive thermal expansion along intermolecular [2\,+\,2] cycloaddition bonds and negative thermal expansion along intermolecular C$-$C single bonds by varying the structural frameworks of molecules. The microscopic mechanism originates from a combination of the framework's geometric flexibility and its transverse vibrational characteristics. Based on this insight, we find molecular networks beyond C$_{60}$ with tunable thermal expansion. These findings shed light on the fundamental mechanisms governing thermal expansion in molecular networks towards rational materials design.

[26] arXiv:2504.08692 (替换) [中文pdf, pdf, html, 其他]

标题： 微波相位锁定在布洛赫晶体管中 显示英文标题

标题： The microwave phase locking in Bloch transistor

Ilya Antonov, Rais Shaikhaidarov, Kyung Ho Kim, Dmitry Golubev, Sven Linzen, Evgeni V. Il'ichev, Vladimir N. Antonov, Oleg V. Astafiev

评论： 6页，4图

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 超导性 (cond-mat.supr-con)

我们报告观察到两种相干量子现象，即约瑟夫森结（JJ）中的电流量子化和Aharonov-Cashier效应。 两种效应的协同作用表现为JJ与微波引起的振荡电荷的相位锁定（电流量子化），以及通过栅极电极的静态电荷对相位锁定现象的控制（Aharonov-Cashier效应）。 实验系统由两个耦合的JJs在相干量子相位滑移的范围内组成。 当施加微波时，I - V曲线上会出现量子化电流平台。 这种效应与JJs中的Shapiro电压台阶相对应。 我们通过栅极电极产生的静态电荷来调节量子化电流。 从概念上讲，该系统具有Bloch晶体管的功能：它可以向量子电路提供受栅极控制的量子化非耗散电流。 显示英文摘要

We report on observation of two coherent quantum phenomena, the current quantization in theJosephson Junction (JJ) and the Aharonov-Cashier effect. The synergy of two effects is seen as the phase locking of the JJ with the oscillating charge engaged by the microwaves (the current quantization), and a control of the phase locking phenomenon with the static charge of the gate electrode (the Aharonov-Cashier effect). The experimental system consists of two coupled JJs in the regime of coherent quantum phase slip. When the microwave is applied, the quantized current plateaus appear on the I - V curve. The effect is dual to the Shapiro voltage steps in JJs. We modulate the quantized current with the static charge induced by the gate electrode. Conceptually, the system has the functionality of the Bloch Transistor: it can deliver gate-controlled quantized non-dissipative current to the quantum circuit.

[27] arXiv:2505.17232 (替换) [中文pdf, pdf, html, 其他]

标题： 可调谐的分子聚集体耦合石墨烯光电晶体管中的光栅效应 显示英文标题

标题： Tunable photogating in a molecular aggregate coupled graphene phototransistor

Abhinav Raina, Maurizio Sanfilippo, Chang-Ki Moon, Manuel Neubauer, Klaus Meerholz, Malte C. Gather, Klas Lindfors

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 光学 (physics.optics)

我们展示了一个与聚合有机半导体层耦合的石墨烯光电探测器。 一个石墨烯光电晶体管被一层微晶分子薄膜覆盖。 分子层的聚集可以通过沉积参数和沉积后的退火来控制，以获得从无定形到高度聚集状态的薄膜。 分子层具有单轴结构，其激子跃迁的跃迁偶极矩是明确的。 分子层的存在导致光电晶体管的响应显著增加。 我们进一步证明，信号增强是由于石墨烯的p型光掺杂。 光谱光响应表明，通过单体和分子聚集体的光掺杂发生方式不同。 我们的光电探测器是一个平台，用于研究分子聚集和有序度对聚合有机半导体与二维材料之间电荷传输过程的影响。 显示英文摘要

We present a graphene photodetector coupled to a layer of aggregated organic semiconductor. A graphene phototransistor is covered with a thin film of merocyanine molecules. The aggregation of the molecular layer can be controlled by the deposition parameters and post-deposition annealing to obtain films ranging from amorphous to a highly aggregated state. The molecular layer has a uniaxial structure with excitonic transitions whose transition dipole moments are well defined. The presence of the molecular layer results in an enormous increase in the response of the phototransistor. We further demonstrate that the signal-enhancement is due to p-photodoping of the graphene. The spectroscopic photoresponse suggests that the photodoping via monomers and molecular aggregates takes place differently. Our photodetector is a platform to study the influence of molecular aggregation and order on charge transport processes between aggregated organic semiconductors and two-dimensional materials.

[28] arXiv:2505.24617 (替换) [中文pdf, pdf, html, 其他]

标题： 用波导装置探测涌现的轴子电动力学 显示英文标题

标题： Probing emergent axion electrodynamics with waveguide apparatus

André H. Gomes, Winder A. Moura-Melo

评论： 清晰度的微小改进

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 高能物理 - 现象学 (hep-ph) ; 光学 (physics.optics)

我们证明，一种常规的空心导体波导，其中填充的材料表现出手性磁效应和反常量子霍尔效应的共存，能够支持横向电磁模的传播。 这种简单的设置提供了一种直接且光学可行的方法来探测这些现象的同时存在，可能有助于在凝聚态系统中检测出现的类轴子场。 显示英文摘要

We demonstrate that a conventional hollow conductor waveguide filled with a material exhibiting the coexistence of chiral magnetic and anomalous quantum Hall effects supports the propagation of transverse electromagnetic modes. This simple setup provides a direct and optically feasible method to probe the simultaneous presence of these phenomena, potentially enabling the detection of an emergent axion-like field within condensed matter systems.

[29] arXiv:2506.17026 (替换) [中文pdf, pdf, html, 其他]

标题： 分散耦合非线性纳米机械模式中的多稳态和噪声诱导的跃迁 显示英文标题

标题： Multistability and Noise-Induced Transitions in Dispersively-Coupled Nonlinear Nanomechanical Modes

David Allemeier, İsmet İnönü Kaya, M. Selim Hanay, Kamil L. Ekinci

期刊参考： 物理评论A（2025）112，023505

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 混沌动力学 (nlin.CD) ; 应用物理 (physics.app-ph)

我们研究了纳米机械梁的两个耦合双稳态模式的噪声动力学。 当解耦时，每个驱动模式遵循杜芬运动方程，在频域中具有明确的双稳态区域。 当两个模式都被驱动时，由于模态频率的振幅依赖性，出现模态间色散耦合，并导致两个模式的耦合状态。 通过在添加噪声的情况下扫描两个模式的驱动频率，我们描绘了系统的动力学行为。 系统在每种频率组合下采样所有可访问的状态，每个稳定状态的概率与其在稳态下的占用时间成正比。 在频域中，系统表现出四个稳定的区域——每个耦合状态一个——这些区域由五条曲线分隔。 这些曲线类似于平衡相图中的共存曲线：每条曲线由稳健的态间转换定义，系统处于两个相邻态的概率相等。 值得注意的是，这些曲线在两个三重点相交，此时系统现在在三个不同的相邻态之间转换。 可以在这非平衡系统和多相热力学系统之间建立物理类比，可能在计算、精密传感和信号处理中有应用。 显示英文摘要

We study the noisy dynamics of two coupled bistable modes of a nanomechanical beam. When de-coupled, each driven mode obeys the Duffing equation of motion, with a well-defined bistable region in the frequency domain. When both modes are driven, intermodal dispersive coupling emerges due to the amplitude dependence of the modal frequencies and leads to coupled states of the two modes. We map out the dynamics of the system by sweeping the drive frequencies of both modes in the presence of added noise. The system then samples all accessible states at each combination of frequencies, with the probability of each stable state being proportional to its occupancy time at steady state. In the frequency domain, the system exhibits four stable regions -- one for each coupled state -- which are separated by five curves. These curves are reminiscent of coexistence curves in an equilibrium phase diagram: each curve is defined by robust inter-state transitions, with equal probabilities of finding the system in the two contiguous states. Remarkably, the curves intersect in two triple points, where the system now transitions between three distinct contiguous states. A physical analogy can be made between this nonequilibrium system and a multi-phase thermodynamic system, with possible applications in computing, precision sensing, and signal processing.

[30] arXiv:2507.21993 (替换) [中文pdf, pdf, html, 其他]

标题： 非凸动能的量子一致处理 显示英文标题

标题： Consistent quantum treatments of non-convex kinetic energies

C. Koliofoti, M. A. Javed, R.-P. Riwar

评论： 5页，2图，附录。正文修改。欢迎提供反馈

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 超导性 (cond-mat.supr-con) ; 量子物理 (quant-ph)

寻找量子哈密顿量与经典拉格朗日量之间一致关系的任务对于基本但普遍的技术如正则量子化和路径积分至关重要。 非凸动能（例如出现在非线性电容器或经典时间晶体中）提出了一个根本性问题：勒让德变换是不明确的，而更一般的勒让德-芬切尔变换通过定义消除了非凸性。 我们认为这种异常理论来自于良好定义的谐波理论的适当低能近似，我们证明了看似不一致的哈密顿量和拉格朗日描述都可以有效，这取决于与耗散环境的耦合强度。 在虚时间中涉及特殊点的情况下，会发生从非凸哈密顿量到凸拉格朗日区的耗散相变。 因此，我们的方法解决了明显的不一致性，并提供了计算上高效的方法来处理异常的、非凸动能。 显示英文摘要

The task of finding a consistent relationship between a quantum Hamiltonian and a classical Lagrangian is of utmost importance for basic, but ubiquitous techniques like canonical quantization and path integrals. Nonconvex kinetic energies (which appear, e.g., in nonlinear capacitors or classical time crystals) pose a fundamental problem: the Legendre transformation is ill-defined, and the more general Legendre-Fenchel transformation removes nonconvexity essentially by definition. Arguing that such anomalous theories follow from suitable low-energy approximations of well-defined, harmonic theories, we show that seemingly inconsistent Hamiltonian and Lagrangian descriptions can both be valid, depending on the coupling strength to a dissipative environment. There occurs a dissipative phase transition from a nonconvex Hamiltonian to a convex Lagrangian regime, involving exceptional points in imaginary time. Our approach thus resolves apparent inconsistencies and provides computationally efficient methods to treat anomalous, nonconvex kinetic energies.

[31] arXiv:2508.15723 (替换) [中文pdf, pdf, html, 其他]

标题： 具有$p$波磁体的交替磁体结处的方向依赖异常霍尔和自旋霍尔电流 显示英文标题

标题： Orientation dependent anomalous Hall and spin Hall currents at the junctions of altermagnets with $p$-wave magnets

Sachchidanand Das, Abhiram Soori

评论： 8页，6幅带说明的图。欢迎提出意见

主题： 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci)

我们使用一个连续模型，研究在反铁磁体（AM）和$p$波磁体（PM）之间的结中电荷和自旋输运，该模型的边界条件针对两种材料的自旋分裂能带结构进行了定制。值得注意的是，尽管 AM 和 PM 都不是自旋极化的，但我们发现该结支持纵向和横向的有限自旋电流。我们计算了纵向和横向电荷和自旋电导率，作为晶体取向以及 AM 和 PM 的奈尔矢量之间相对角度的函数。我们的结果表明，即使纵向电荷电导率为零，横向电荷和自旋电导率也可以是有限的。对于合适的参数选择和取向角度，横向电导率比纵向电导率更显著。这些效应的根源在于结两侧横向动量模式（$k_y$）的匹配与不匹配，以及 AM 和 PM 中的自旋依赖能带分裂。此外，虽然对于某些取向，横向电荷电导率可能会抵消，但由于相反的$k_y$通道贡献不均，横向自旋电导率仍然保持有限。这些发现突显了反铁磁体-$p$波磁体结作为一个有前途的平台，可用于纯由晶体取向和自旋结构驱动的可调横向电荷和自旋电流的生成和控制。 显示英文摘要

We study charge and spin transport across a junction between an altermagnet (AM) and a $p$-wave magnet (PM) using a continuum model with boundary conditions tailored to the spin-split band structures of the two materials. Remarkably, although neither AM nor PM is spin-polarized, we find that the junction supports finite spin currents both longitudinally and transversely. We compute the longitudinal and transverse charge and spin conductivities as functions of the crystallographic orientations and the relative angle between the Neel vectors of AM and PM. Our results reveal that transverse charge and spin conductivities can be finite even when the longitudinal charge conductivity vanishes. For suitable parameter choices and orientation angles, the transverse conductivities are more prominent than the longitudinal ones. The origin of these effects lies in the matching and mismatching of transverse momentum modes ($k_y$) across the junction combined with the spin-dependent band splitting in AM and PM. Furthermore, while the transverse charge conductivity may cancel for certain orientations, the transverse spin conductivity remains finite due to unequal contributions of opposite $k_y$ channels. These findings highlight altermagnet-$p$-wave magnet junctions as a promising platform for tunable generation and control of transverse charge and spin currents driven purely by crystallographic orientation and spin structure.

[32] arXiv:2410.18543 (替换) [中文pdf, pdf, html, 其他]

标题： 用混合超导量子器件抑制混沌 显示英文标题

标题： Suppressing chaos with mixed superconducting qubit devices

Ben Blain, Giampiero Marchegiani, Luigi Amico, Gianluigi Catelani

评论： 13页，11图

期刊参考： 物理评论应用 24, 014048 (2025)

主题： 量子物理 (quant-ph) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

在量子信息处理中，两种不同的任务之间会出现矛盾：虽然通过隔离量子比特可以保持其状态，但量子门只能通过量子比特之间的相互作用来实现。 在量子比特阵列中，弱耦合会导致状态空间局域化，而强耦合会导致非局域化状态。 在此，我们研究平均能级间距以及能级间距分布的相对熵（与泊松分布和高斯正交系综的Kullback-Leibler散度），以分析超导量子比特线性阵列中局域化与非局域化（混沌）区域之间的转变。 我们考虑了transmon量子比特以及电容分流通量量子比特，这使我们能够调节量子比特的非谐性。 由仅包含transmon或通量量子比特的均匀非谐性阵列显示出非常相似的能级统计特性与耦合强度的关系。 在具有交替非谐性的系统中，对于典型的量子比特频率无序，发现局域化区域在量子比特-量子比特耦合强度增加时比仅含一种量子比特类型的阵列更具韧性。 我们的结果也通过广义的玻色-哈伯德模型得到了验证，这些结果支持设计包含不同量子比特类型的器件，以实现更高的性能。 显示英文摘要

In quantum information processing, a tension between two different tasks occurs: while qubits' states can be preserved by isolating them, quantum gates can be realized only through qubit-qubit interactions. In arrays of qubits, weak coupling leads to states being spatially localized and strong coupling to delocalized states. Here, we study the average energy level spacing and the relative entropy of the distribution of the level spacings (Kullback-Leibler divergence from Poisson and Gaussian Orthogonal Ensemble) to analyze the crossover between localized and delocalized (chaotic) regimes in linear arrays of superconducting qubits. We consider both transmons as well as capacitively shunted flux qubits, which enables us to tune the qubit anharmonicity. Arrays with uniform anharmonicity, comprising only transmons or flux qubits, display remarkably similar dependencies of level statistics on the coupling strength. In systems with alternating anharmonicity, for typical disorder in the qubit frequencies the localized regime is found to be more resilient to the increase in qubit-qubit coupling strength in comparison to arrays with a single qubit type. Our results, which we also confirm using generalized Bose-Hubbard models, support designing devices that incorporate different qubit types to achieve higher performances.

[33] arXiv:2410.18559 (替换) [中文pdf, pdf, html, 其他]

标题： 几何分形中非遍历多分形量子态的出现 显示英文标题

标题： Emergence of non-ergodic multifractal quantum states in geometrical fractals

Fabio Salvati, Mikhail I. Katsnelson, Andrey A. Bagrov

评论： 少量修改；扩展了补充材料。正文中有28页，包含9幅图，补充材料中有19幅图。

主题： 无序系统与神经网络 (cond-mat.dis-nn) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 量子物理 (quant-ph)

本征态多分形性是非相互作用无序金属的显著特征，也可能在多体局域化态中观察到，其特点是异常缓慢的动力学行为，并且对量子物理的许多领域具有相关性，从测量驱动系统到超导性。 我们提出一种新方法，通过在晶体晶格中迭代引入缺陷，从而在无无序的情况下实现非遍历多分形态（NEMs），将结构从普通结构重塑为分形几何。 通过对谢尔宾斯基垫片案例的综合分析，我们发现了NEMs出现的有力证据，这些NEMs超越了传统量子态的分类，并为量子输运研究指明了新途径。 我们讨论了这些态的潜在实验特征。 显示英文摘要

Eigenstate multifractality, a hallmark of non-interacting disordered metals, which may also be observed in many-body localized states, is characterized by anomalous slow dynamics and appears relevant for many areas of quantum physics, from measurement-driven systems to superconductivity. We propose a novel approach to achieve non-ergodic multifractal states (NEMs) without disorder by iteratively introducing defects into a crystal lattice, reshaping it from a plain structure into a fractal geometry. By comprehensive analysis of the Sierpi\'nski gasket case, we find robust evidence of the emergence of NEMs that go beyond the conventional classification of quantum states and designate new pathways for quantum transport studies. We discuss potential experimental signatures of these states.

[34] arXiv:2411.16862 (替换) [中文pdf, pdf, html, 其他]

标题： 拓扑能带对晶格势和杂质的鲁棒平移不变性 显示英文标题

标题： Robust translational invariance in topological bands against lattice potentials and disorders

Bo Peng, Nilanjan Roy, Guangyue Ji, Bo Yang

期刊参考： 物理评论B 112, L081114 (2025)

主题： 强关联电子 (cond-mat.str-el) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

我们从理论上证明，单个Landau能级(LL)的Hilbert(子)空间内的连续磁性平移不变性即使在存在超晶格静电势调制的情况下也能持续存在，而在整个实空间Hilbert空间中这种不变性会被破坏。 这是由于超晶格常数与量子霍尔流体的基本长度尺度之间的相互作用。 特别是对于最低的LL（LLL），当超晶格间距小于磁长度时，连续的磁性平移对称性非常稳健。 对于分数量子霍尔相，当超晶格间距小于我们现在已经可以定量定义的相应基本长度时，连续的平移对称性得以保持，这与来自量子度量的长度尺度不同。 此外，我们的分析表明，任意子激发的动力学可以对无序的长波部分具有鲁棒性，并且我们讨论了相关的实验影响。 显示英文摘要

We theoretically show that the continuous magnetic translational invariance within the Hilbert (sub-)space of a single Landau level (LL) can persist even in the presence of a superlattice electrostatic potential modulation, while such invariance is broken in the full real-space Hilbert space. This is due to the interplay of the superlattice constant and the fundamental length scale of the quantum Hall fluids. In particular for the lowest LL (LLL), when the spacing of superlattice is below the magnetic length, continuous magnetic translational symmetry is very robust. For the fractional quantum Hall phases, the continuous translational symmetry is preserved when the superlattice spacing is below the corresponding fundamental lengths which we can now quantitatively define, which is different from the length scale from the quantum metric. Moreover, our analysis implies that the dynamics of the anyonic excitations can be robust against the long wavelength part of the disorder, and we discuss the related experimental ramifications.

[35] arXiv:2412.14600 (替换) [中文pdf, pdf, html, 其他]

标题： 通过体-边对应关系识别拓扑激子绝缘体 显示英文标题

标题： Identifying topological excitonic insulators via bulk-edge correspondence

Hongwei Qu, Zeying Zhang, Yuanchang Li

评论： 被PRB接受

主题： 强关联电子 (cond-mat.str-el) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

激子绝缘体仍然难以捉摸，且缺乏可靠的识别方法。 在本工作中，我们展示了拓扑激子绝缘体在识别方面的前景，因为它们具有独特的体-边对应关系，如LiFe$X$ ($X$ = S, Se, 和 Te) 家族所示。 第一性原理Bethe-Salpeter方程计算揭示了这些自旋轨道耦合量子反常霍尔绝缘体中的激子不稳定性。 有效哈密顿量分析表明，自发激子凝聚不会破坏无能隙的边缘态，而是将体能隙重构为几乎与自旋轨道耦合强度无关。 这种体-边对应关系的变化可以通过角分辨光电子能谱或电子压缩性测量进行实验检测，为拓扑激子绝缘体的识别提供了观察证据。 此外，激子凝聚将拓扑非平凡相的临界温度提高到了室温以上。 显示英文摘要

Excitonic insulator remains elusive and there has been a lack of reliable identification methods. In this work, we demonstrate the promise of topological excitonic insulators for identification due to their unique bulk-edge correspondence, as illustrated by the LiFe$X$ ($X$ = S, Se, and Te) family. First-principles Bethe-Salpeter equation calculations reveal excitonic instabilities in these spin-orbit coupling quantum anomalous Hall insulators. Effective Hamiltonian analyses indicate that spontaneous exciton condensation does not disrupt the gapless edge state but reconstructs the bulk-gap to be almost independent of the spin-orbit coupling strength. This change in the bulk-edge correspondence can be experimentally inspected by angle-resolved photoelectron spectroscopy or electron compressibility measurements, providing observational evidence for the identification of topological excitonic insulators. Moreover, exciton condensation raises the critical temperature of the topological nontrivial phase above room temperature.

[36] arXiv:2501.16486 (替换) [中文pdf, pdf, 其他]

标题： 相位匹配的电子-光子相互作用由三维打印的螺旋波导实现 显示英文标题

标题： Phase-matched electron-photon interactions enabled by 3D-printed helical waveguides

Masoud Taleb, Mohsen Samadi, Nahid Talebi

主题： 光学 (physics.optics) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

史密斯-珀塞尔效应通过将光学光栅的衍射级次与运动电子的近场进行相位匹配，实现了跨任意光谱范围的电磁辐射。 在本工作中，我们引入了一种新方法，使用螺旋形波导，其中相位匹配是通过在通过三维打印机使用双光子聚合制造的螺旋光纤中引导的光实现的。 我们的结果表明，这些结构产生的辐射精确满足相位匹配条件，并在特定角度上定向发射，这与传统史密斯-珀塞尔效应的宽广角度分布特性形成对比。 螺旋电子驱动的光子源建立了一个新范式，使3D打印结构能够控制电子束诱导的辐射，并反过来促进光诱导的高效电子束整形和加速。 显示英文摘要

The Smith-Purcell effect enables electromagnetic radiation across arbitrary spectral ranges by phase-matching the diffraction orders of an optical grating with the near-field of a moving electron. In this work, we introduce a novel approach using a helically shaped waveguide, where phase-matching is achieved through guided light within a helical optical fiber fabricated via two-photon polymerization using a 3D printer. Our results demonstrate that radiation from these structures precisely satisfies the phase-matching condition and is emitted directionally at specific angles, contrasting with the broad angular distribution characteristic of the traditional Smith-Purcell effect. Helical electron-driven photon sources establish a new paradigm, enabling 3D-printed structures to control electron-beam-induced radiation and, inversely, to facilitate light-induced efficient electron beam shaping and acceleration.

[37] arXiv:2502.13072 (替换) [中文pdf, pdf, html, 其他]

标题： 约瑟夫森结势垒变化分析——一种结合电子显微镜、击穿和蒙特卡洛的方法 显示英文标题

标题： Analysis of Josephson Junction Barrier Variation -- a Combined Electron Microscopy, Breakdown and Monte-Carlo Approach

Oscar W. Kennedy, Kevin G. Crawford, Kowsar Shahbazi, Connor D. Shelly

评论： 8个主页面，5个主图，1张表，附录SI

主题： 量子物理 (quant-ph) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall) ; 材料科学 (cond-mat.mtrl-sci) ; 应用物理 (physics.app-ph)

制造公差严格的约瑟夫森结是超导量子计算的必要组件。 开发约瑟夫森结的精确制造技术需要了解其组成结构，并建立稳健的反馈指标以进行优化。 在此，我们考虑互补技术，评估它们能让我们对结中的势垒得出什么结论。 对势垒的蒙特卡洛模拟表明，总势垒厚度的15-20%的标准偏差与我们的实验数据相容。 电气击穿使我们能够探测势垒中最薄弱的部位。 缩小这种击穿的分布为势垒优化提供了一种有前景的反馈机制。 按击穿电压对结进行分组，使我们能够识别具有不同中位电阻的子集合。 透射电子显微镜可用于查找平均势垒厚度，尽管我们强调从这些实验中得出势垒厚度分布的稳健结论存在挑战。 显示英文摘要

Josephson junctions manufactured to tight tolerances are necessary components for superconducting quantum computing. Developing precise manufacturing techniques for Josephson junctions requires an understanding of their make-up and robust feedback metrics against which to optimise. Here we consider complementary techniques assessing what conclusions they allow us to draw about the barriers in junctions. Monte-Carlo simulations of barriers show that standard deviations of 15-20% of the total barrier thickness are compatible with our experimental data. Electrical breakdown allows us to probe the weakest points in barriers. Narrowing the distribution of this breakdown provides a promising feedback mechanism for barrier optimisation. Grouping junctions by breakdown voltage allows us to identify sub-ensembles of junctions with different median resistance. Transmission electron microscopy can be used to find average barrier thickness, although we highlight challenges forming robust conclusions on the distribution of thicknesses in a barrier from these experiments.

[38] arXiv:2503.23593 (替换) [中文pdf, pdf, html, 其他]

标题： 基于量子点的相干自旋-光子接口中的测量诱导反作用 显示英文标题

标题： Measurement-induced back-action in a QD-based coherent spin-photon interface

Adrià Medeiros, Manuel Gundín, Dario A. Fioretto, Vincent Vinel, Eliott Rambeau, Elham Mehdi, Niccolo Somaschi, Aristide Lemaître, Isabelle Sagnes, Nadia Belabas, Olivier Krebs, Pascale Senellart, Loïc Lanco

主题： 量子物理 (quant-ph) ; 中尺度与纳米尺度物理 (cond-mat.mes-hall)

极化编码的自旋-光子接口是发展用于光子接收器的静态节点的有前途的候选方案，用于量子通信和分布式量子计算。 在这里，我们引入了一种时间分辨层析成像方法，该方法允许观察半导体量子点中的电子自旋动力学，并将其映射到反射光子的偏振态的动力学。 通过一次层析成像实验，我们可以推断出所有相关的自旋动力学时间尺度，包括进动、退相干和弛豫时间。 我们还演示并量化了由检测单个反射光子引起的对嵌入式自旋量子比特的测量反作用。 我们表明，通过选择测量的偏振基，可以调节所诱导的自旋态的激发态和相干性。 对嵌入式自旋量子比特的光子诱导反作用的控制构成了将自旋-光子接口用作量子接收器的关键要求。 显示英文摘要

Polarization-encoded spin-photon interfaces constitute promising candidates for the development of stationary nodes used as photon receivers, for quantum communication and distributed quantum computing. Here we introduce a time-resolved tomography approach which allows observing the dynamics of an electron spin, in a semiconductor quantum dot, mapped onto the dynamics of the polarization state of reflected photons. Through a single tomography experiment, we infer all the relevant spin dynamics timescales, including precession, decoherence and relaxation times. We also demonstrate and quantify the measurement back-action induced, on the embedded spin qubit, by the detection of a single reflected photon. We show that the induced population and coherence of the spin state can be tuned by the chosen polarization basis of the measurement. The control of the photon-induced back-action on the embedded spin qubit constitutes a crucial requirement for the use of spin-photon interfaces as quantum receivers.