基于Λ型三能级原子系统的单向放大研究

Unidirectional Amplification with Simple Lambda-Type Three-Level Atomic System

单向放大在光信号处理与光通信中扮演着不可或缺的角色,其既可以对信号光进行放大,也可以为避免信号源受到反向杂散光影响提供一种关键的保护手段。基于Λ型三能级原子系统实现了光场的单向放大,在铷原子气体中,仅用一束控制场,在实验上获得了前向25 dB的增益和后向超过30 dB的隔离度;同时,探讨了铷气室温度和控制场强度对单向放大的影响。

Unidirectional amplification of light plays an indispensable role in optical signal processing and optical communication.It can not only amplify the signal light,but also provide a key protection to avoid the signal being affected by the reverse stray light.In this paper,unidirectional amplification of light is achieved with the simple Lambda-type three-level atomic system.Using only one control field,a gain of more than 25 dB for the forward signal and an isolation of more than 30 dB for the backward one is realized using the rubidium atomic gas.Furthermore,the effects of the rubidium cell temperature and the intensity of the control field on the unidirectional amplification are also investigated in detail.