Optical echo memory based on photonic crystal cavities

Xue-Yan Xing,Xia-Xia Li,Xiang-Dong Zhang,Yu-Hui Chen

doi:10.7498/aps.71.20220083

Abstract

Like internet, connecting quantum computers together to build a full quantum network will enhance the ability to process quantum information. On-chip quantum memories can possess the essential functionalities in building a quantum network, including synchronizing a large number of quantum computers and implementing long-distance quantum communication. However, owning mainly to the constraints imposed by the micro-photonic structures themselves, on-chip quantum memories cannot satisfy the requirement for constructing the full quantum network for the incompatibility of their memory property and integration property. We here propose to build an on-chip quantum memory by using spatial-phase-mismatching effect in photonic crystal cavities. In this scenario, not only is the large orbital angular momentum of photonic crystal cavities utilized to realize photon-echo type memory, but also the light-matter enhancement of a photonic cavity is used to achieve a high-efficiency quantum storage.

Highlights

存储技术主要包括梯度回波存储 (gradient echo memory, GEM) 技术[12]、受控非均匀线宽反转 (controlled reversible inhomogeneous broadening, CRIB) 技术 [13−15] 和原子频率梳 (atomic frequency comb, AFC) 技术 [16]
Protocol of ROSE quantum memory based on photonic crystal structures: (a) One photonic crystal structure that is suitable for ROSE technique; (b) a signal pulse is input from the left, and the collective atomic polarization has a “clockwise” spatial phase distribution φ0(r); (c) control π pulses are input from the right, have a “anti-clockwise” spatial phase distribution φ1(r); (d) after the second π pulse, according the Eqs. (13) and (15), the collective atomic polarization has a phase distribution of φ0(r) and emit a photon echo to the right port

Summary

Introduction

存储技术主要包括梯度回波存储 (gradient echo memory, GEM) 技术[12]、受控非均匀线宽反转 (controlled reversible inhomogeneous broadening, CRIB) 技术 [13−15] 和原子频率梳 (atomic frequency comb, AFC) 技术 [16]. 然而, 目前对于 ROSE 存储技术的讨论主要集中在宏观尺寸或者是光场具有明确的传播方向的结构上, 如环形光学谐振腔或者波导结构 [9,23,24]. 原子系统的动力学过程由薛定谔方程给出: d a(t) = − i Ω(r, t)eiφ(r) · b(t), dt d b(t) = −i ∆ b − i Ω(r, t)e−iφ(r) · a(t). A(t) = cos Ωt a(0) − ieiφ(r) sin Ωt b(0), ()

Results

Conclusion