铯原子激发态超窄带宽光学滤波器研究  

Experimental Study on Ultra⁃narrow Bandwidth Optical Filters with Excited States of Cesium Atoms

作　　者：赵韩帅 杨保东[1,2,3] 薛朝 郑蓝蓝 Zhao Hanshuai;Yang Baodong;Xue Zhao;Zheng Lanlan(College of Physics and Electronic Engineering,Shanxi University,Taiyuan 030006,Shanxi,China;State Key Laboratory of Quantum Optics and Quantum Optics Device,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,Shanxi,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,Shanxi,China)

机构地区：[1]山西大学物理电子工程学院,山西太原030006 [2]山西大学光电研究所,量子光学与光量子器件国家重点实验室,山西太原030006 [3]山西大学极端光学协同创新中心,山西太原030006

出　　处：《中国激光》2024年第5期120-127,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(61975102);山西省自然科学基金(20210302123437);山西省高等学校科技创新项目(2019L0101)。

摘　　要：基于铯原子6S_(1/2)-6P_(3/2)-6D_(5/2)(852 nm+917 nm)阶梯型能级结构,以波长为852 nm圆偏振光作为泵浦光,将原子由基态6S_(1/2)布居到中间激发态6P_(3/2),并将原子介质极化。波长为917 nm线偏振光作为信号光通过极化的原子介质后,其偏振面发生了旋转,从而实现了工作波长为917 nm非线性光学滤波器。实验上详细测量、分析了泵浦光功率、原子气室温度,以及泵浦光与信号光同、反向实验构型对该非线性光学滤波器性能的影响,在优化的实验参数下,该滤波器的峰值透射率可达20%,等效噪声带宽<60 MHz。超窄带宽的光学滤波器在原子钟、自由空间光通信、激光遥感系统等领域具有潜在的应用价值。Objective Atomic optical filters have a broad range of applications in several areas,including atomic clocks,free-space optical communications,and laser remote sensing systems.The Faraday anomalous dispersion optical filter(FADOF)is one of the most popular optical filters because of its narrow bandwidth,high transmission,fast response,and high noise rejection.As a result,it has been intensively studied both theoretically and experimentally.The FADOF is based on the rotation of the polarization direction of a linearly polarized light signal when it passes through an atomic medium in a magnetic field.Most previously published studies have focused on the FADOF of the atomic transition between the ground and excited states;consequently,the selectivity of the operating wavelength of the FADOF is often limited.Some scholars have further investigated the FADOF between two excited states(ESFADOF),owing to their abundant transitions.However,the bandwidths of the FADOF and ES-FADOF are usually of the order of~GHz.Currently,the investigation of atomic optical filters with ultranarrow bandwidths remains a focus.Methods Based on a ^(133)Cs 6S_(1/2)-6P_(3/2)-6D_(5/2)(852 nm+917 nm)ladder-type atomic system,we present an experimental study on a nonlinear optical filter with an ultra-narrow bandwidth,as shown in Fig.1.A circularly polarized laser with a wavelength of 852 nm was used as the pump light to populate the atoms from the ground state 6S_(1/2) to the intermediate excited state 6P_(3/2) and to polarize the atomic medium.The polarization direction of the 917 nm linearly polarized laser as the signal light,with a frequency in the vicinity of the 6P_(3/2)-6D_(5/2) transition,was rotated when it passed through the polarized atomic medium.The experimental setup is shown in Fig.2.The temperature-controlled ^(133)Cs vapor cell was placed between a pair of Glan-Taylor prisms with perpendicular polarization directions;the extinction ratio of the prisms reached 100000∶1.The 852 nm pump and 917 nm signal lights overlapped in the

关 键 词：滤光器 非线性光学效应 激发态 遥感 

分 类 号：O562[理学—原子与分子物理]