关联调制PT对称原子系统中光子传输行为的量子调控与应用

Recently the PT-symmetric optical system is becoming a new research hotspot and has been widely applied in research fields of the quantum information processing and the novel device design. In this project, we will exactly use double-period correlative modulation to establish a novel dual-light PT-symmetric atomic metamaterial in cold atomic ensembles driven by double cooperatively controlled standing-wave lasers, and comprehensively explore optical responses of this system in the position space and the momentum space. 1) In the position space, we would like to study the double light dynamic propagation in the PT-symmetric atomic ensemble, and then realize the dynamic non-reciprocal dual-light memory arising from stationary light pulses. 2) We will also study the PT-symmetric properties of this atomic ensemble in the momentum space and then achieve the multi-dimension supperradiance lattice to provide an optical manipulation platform for photonic transport in some quantum phenomena observed. 3) Based on those above works, we will construct a flat-band network structure by properly setting multiple atomic ensembles considered; With the methods summarized for analyzing the position-space and momentum-space optical properties of this PT-symmetric atomic system, then we will study properties of this network such as optical non-reciprocity and energy dispersion to observe the Landau-Zener Bloch oscillation, realize its PT -symmetry operation and then grasp its underlying physical meaning; With this novel oscillation, we aim to realize unconventional multi-photon propagation and storage between these lattices. Our results will develop applications of the PT-symmetric optical system for quantum manipulation such as providing a feasible plan of the multi-photon signal transport, storage and processing in optical networks.

PT对称光学系统在量子信息处理、新型器件设计等领域都有广泛应用，其研究倍受关注。本项目旨在控制一对驻波激光对冷原子系综进行双周期关联调制，构造新型可双光探测的PT对称原子超材料，对其位置、动量空间光特性进行全面分析。1）分析建立的PT对称单原子系综在位置空间的双光子传播过程，实现具有光不互惠性的静态光脉冲式光存储。2）研究该单原子系综动量空间的PT对称特性，实现多维超辐射晶格，为一些量子现象中独特的光子传输行为提供调控平台。3）利用多个原子系综构造具有平坦能带的网格结构，基于已获得的位置、动量空间光特性的研究方法，分析该网格的光不互惠、能带色散等特性，实现 Landau-Zener布洛赫振荡并对其进行PT操作，进一步分析这种新型振荡的物理意义，并利用其实现格点间非传统的多光子传播与存储。项目结果将拓展PT对称光学系统在量子调控方面的应用，提供新型的光网络中多光信号传输、存储与处理机制。

近年来，对以PT对称光学等理论构造非厄密的原子、光力学等多形式光学系统的研究，在量子调控有着广泛应用，成为促进量子信息处理、光子网络等领域发展的重要理论基础。本项目构造包含驻波的多种光场耦合的冷原子、与原子耦合的光力学系统等多种模型，从而搭建低维晶格系统，基于电磁感应透明、光学PT对称、Landau-Zener布洛赫振荡等实现非传统的光子调控机制，如非互惠光传输等，提出有效的光子存储、光子路由、光子二极管等有效方案。利用驻波耦合原子晶格建立双周期关联调制，实现三色的光子带隙式调控。其强反射对于晶格缺陷具有强鲁棒性。有助探索设计多色光子的全光开关和光子路由等光学器件。以原子为基础，用两个互相垂直双微腔驻波耦合，当两子系统处于增益损耗平衡条件时，构造光学PT对称。在PT对称破缺相变点附近，该系统输出场的线性、非线性部分均明显增益。该方案易于实现，为研究低能光的PT对称光学提供良好的研究平台，且该原子-腔耦合诱导的非线性增益也可用于研发新型的可控非线性光学介质。基于此设计了多模光场耦合的光机械系统，提出一种双栅极光学晶体管有效方案。在一定的参数条件下，由于不同跃迁路径间的量子干涉效应，获得光信号的非互惠放大。通过控制有效光力耦合强度可在该系统中产生可控的快慢光效应，实现快慢光切换且方向可调。该工作为实现非互易光学器件提供了可行的方案。基于已构造系统，拓展研究低维链式晶格结构，尤其超辐射晶格。建立三聚化非厄密晶格系统，分析其动量空间和实空间量子调控特性。通过不对称耦合，对对称或不对称的多光子能带结构进行分析，从而获得具有趋肤效应的不对称拓扑边缘态，这为量子态的高效存储提供有效方案。引入有效Peierls相位，对动量空间能带进行调节，实现光子传输在晶格内的Landau-Zener布洛赫振荡，且该传输对晶格缺陷显出极强鲁棒性。通过设计异质和三文治结构，实现光子存储和光二极管有效机制。