Wen Rong, Zou Chang-Ling, Zhu Xinyu, Chen Peng, Ou Z Y, Chen J F, Zhang Weiping
State Key Laboratory of Precision Spectroscopy, Quantum Institute for Light and Atoms, School of Physics and Materials Science, East China Normal University, Shanghai 200241, China.
Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, Anhui, China.
Phys Rev Lett. 2019 Jun 28;122(25):253602. doi: 10.1103/PhysRevLett.122.253602.
The interference of photons in a lossy beam splitter (BS) exhibits anticoalescence, which is surprising for bosons. Such a non-Hermitian system involving open quantum dynamics is of particular interest for quantum information processing and metrology. The Hermiticity of photonic devices is generally fixed according to the material, but is controllable at the interface of photons and atomic systems. Here, we demonstrate a tunable non-Hermitian BS for the interference between traveling photonic and localized magnonic modes. The crossover from a Hermitian to a non-Hermitian magnon-photon BS is achieved by controlling the coherent and incoherent interaction mediated by the excited levels of atoms, which is reconfigurable via the detuning of a control laser. A correlated interference pattern between the photons and magnons is demonstrated by such a non-Hermitian BS. Our system has the potential to operate with photons and magnons at the single-quanta level, and it provides a versatile quantum interface for studying the non-Hermitian quantum physics and parity-time symmetry.
有损耗分束器（BS）中光子的干涉表现出反聚束现象，这对于玻色子来说是令人惊讶的。这种涉及开放量子动力学的非厄米系统在量子信息处理和计量学方面具有特别的意义。光子器件的厄米性通常由材料决定，但在光子与原子系统的界面处是可控的。在此，我们展示了一种用于行波光子模式与局域磁振子模式之间干涉的可调谐非厄米分束器。通过控制由原子激发态介导的相干和非相干相互作用，实现了从厄米磁振子 - 光子分束器到非厄米磁振子 - 光子分束器的转变，这种相互作用可通过控制激光的失谐进行重构。这种非厄米分束器展示了光子与磁振子之间的相关干涉图样。我们的系统有潜力在单量子水平上对光子和磁振子进行操作，并且它为研究非厄米量子物理和宇称 - 时间对称性提供了一个通用的量子界面。
