标题： 高阶自旋张量霍尔效应中的 cancellation 定理破坏与共振自旋张量霍尔电导率 显示英文标题

标题： Cancellation theorem breaking and resonant spin-tensor Hall conductivity in higher-rank spin-tensor Hall effects

摘要： 随着冷原子中量子现象模拟的最新进展，在自旋张量动量耦合的更大自旋系统中发现了更高秩的自旋张量霍尔效应，这是较大自旋系统中著名的自旋霍尔效应的扩展。此前，有研究表明，具有Rashba自旋轨道耦合的二维电子气可以产生无耗散的横向自旋电流，即自旋霍尔效应。然而，后来的研究表明，自旋电流被顶点修正所抵消，并且该抵消定理随后被证明与散射机制、自旋轨道耦合强度或费米能无关。虽然最近的研究展示了普遍的内在自旋张量霍尔电导率，但尚不清楚它是否会像自旋霍尔效应那样消失。在这项工作中，我们解决了这一关键问题，表明秩-2自旋张量电流可以通过考虑分支间和分支内跃迁的贡献而发散，这在某种意义上类似于量子霍尔效应。因此，在有限尺寸系统中无法观察到\textit{通用的}自旋张量霍尔效应。然而，我们进一步表明，在磁场下朗道能级交叉时，存在\textit{可观测的非零}自旋张量霍尔电导率共振。我们的工作揭示了更大自旋系统的有趣电导特性，并将为更高秩自旋张量霍尔效应的实验探索及其潜在器件应用提供有价值的指导。 显示英文摘要

摘要： With recent advances in simulating quantum phenomena in cold atoms, the higher-rank spin tensor Hall effect was discovered in larger spin systems with spin-tensor-momentum coupling, which is an extension of the celebrated spin Hall effects in larger spins. Previously, it has been proposed that a 2D electron gas with Rashba spin-orbit coupling can generate dissipationless transverse spin current, namely the spin Hall effect. However, later work showed that the spin current is canceled by vertex correction, which was subsequently proven by a cancellation theorem that does not depend on any assumptions related to the scattering mechanism, the strength of spin-orbit coupling, or the Fermi energy. While the recent proposal demonstrates a universal intrinsic spin-tensor Hall conductivity, it is unclear if it vanishes similarly to the spin Hall effect. In this work, we address this critical problem and show that the rank-2 spin-tensor current can be divergent by considering the contributions of both interbranch and intrabranch transitions, which resembles the quantum Hall effect in some sense. So the \textit{universal} spin-tensor Hall effect can not be observed in a system with finite size. However, we further show that there is an \textit{observable non-zero} resonance of spin-tensor Hall conductivity as the Landau levels cross under the magnetic field. Our work reveals interesting conductivity properties of larger-spin systems and will provide valuable guidance for experimental explorations of higher-rank spin-tensor Hall effects, as well as their potential device applications.