标题： 可控制的双光子干涉与通用量子频率处理器 显示英文标题

标题： Controllable two-photon interference with versatile quantum frequency processor

摘要： 量子信息是信息科学的下一个前沿领域，有望实现无条件安全的通信、增强的信道容量以及远超其经典对应物的计算能力。 随着量子信息处理设备持续从实验室走向实际应用，它们之间及其与用户之间的基础基础设施——量子互联网——的需求只会增加。 由于频率复用和控制在经典互联网中的显著成功，光学频率中的量子信息编码与最先进的光纤网络产生了有趣的协同效应。 然而，相干量子频率操作证明极其具有挑战性，这是由于在混合频率时难以高效、任意、并行且低噪声地进行操作。 在这里，我们实施了一种基于可重构量子频率处理器的原创方法，该处理器旨在对光谱编码的量子比特进行任意操作。 该处理器的独特可调性使我们能够以创纪录的94%可见度演示频率-bin Hong-Ou-Mandel干涉。 此外，通过将这种可调性与我们方法的自然并行性相结合，我们在同一设备中合成了独立的量子频率门，实现了在两个纠缠光子上首次高保真度的光谱相关性翻转。 与基于非线性光学的量子频率混合方法相比，我们的线性方法消除了对额外泵浦场的需求，并显著降低了背景噪声。 我们的结果在一个平台上展示了多种功能的并行性，标志着频率复用量子互联网的重大进展。 显示英文摘要

摘要： Quantum information is the next frontier in information science, promising unconditionally secure communications, enhanced channel capacities, and computing capabilities far beyond their classical counterparts. And as quantum information processing devices continue to transition from the lab to the field, the demand for the foundational infrastructure connecting them with each other and their users---the quantum internet---will only increase. Due to the remarkable success of frequency multiplexing and control in the classical internet, quantum information encoding in optical frequency offers an intriguing synergy with state-of-the-art fiber-optic networks. Yet coherent quantum frequency operations prove extremely challenging, due to the difficulties in mixing frequencies efficiently, arbitrarily, in parallel, and with low noise. Here we implement an original approach based on a reconfigurable quantum frequency processor, designed to perform arbitrary manipulations of spectrally encoded qubits. This processor's unique tunability allows us to demonstrate frequency-bin Hong-Ou-Mandel interference with record-high 94% visibility. Furthermore, by incorporating such tunability with our method's natural parallelizability, we synthesize independent quantum frequency gates in the same device, realizing the first high-fidelity flip of spectral correlations on two entangled photons. Compared to quantum frequency mixing approaches based on nonlinear optics, our linear method removes the need for additional pump fields and significantly reduces background noise. Our results demonstrate multiple functionalities in parallel in a single platform, representing a huge step forward for the frequency-multiplexed quantum internet.