Rydberg原子nS1/2→(n+1)S1/2双光子激发EIT-AT光谱

主要研究了热原子蒸气池中铯Rydberg原子nS_1/2→(n+1)S_1/2微波耦合的双光子光谱.铯原子基态(6S_1/2)、第一激发态(6P_3/2)、Rydberg态(69S_1/2)形成阶梯型三能级系统,弱探测光作用于基态到激发态6S_1/2→6P_3/2的跃迁,强耦合光则作用于6P_3/2→69S_1/2的Rydberg跃迁形成电磁感应透明(EIT)效应,实现对Rydberg原子的光学探测.频率fMW=11.735 GHz的微波场耦合69S_1/2→70S_1/2的Rydberg跃迁,形成微波双光子光谱.利用EIT-AT分裂光谱研究微波电场强度对双光子光谱的影响.研究表明:在强微波场作用时,EIT-AT分裂与微波场功率成正比,而弱微波场时的EIT-AT分裂与微波场功率成非线性依赖关系,理论计算与实验测量结果相一致.本文的研究对微波电场的精密测量具有一定的指导意义.

nS1/2→(n+1)S1/2 two-photon excitation EIT-AT spectrum of Rydberg atom

In this work,we present an nS_1/2→(n+1)S_1/2 two-photon excitation EIT-AT spectrum of Rydberg atom in the vapor cell.A ground state(6S_1/2),a first excited state(6P_3/2)and Rydberg state(69S_1/2)of cesium atoms constitute a three-level system.A weak probe laser locking to the transition of 6S_1/2(F=4)→6P_3/2(F′=5)couples the ground-state transition,and the strong coupling laser drives the Rydberg transition of 6P_3/2→69S_1/2 to yield electromagnetically induced transparency(EIT)effect,which realizes the optical detection of Rydberg atoms.Two Rydberg 69S_1/2 and 70S_1/2 levels are coupled with the microwave field at a frequency of fMW=11.735 GHz,forming a microwave two-photon spectrum.To observe the influence of microwave electric field power on two-photon spectrum,we investigate the microwave coupled Rydberg EIT-AT spectra at different microwave fields.The measurements show that the EIT-AT splitting interval is proportional to the square of the microwave electric field at strong microwave field,and indicvates a nonlinear dependence at weak microwave electric field.The theoretical calculation accords with the experimental measurement.The work here is of significance in precisely measuring the microwave electric field.