基于里德伯原子Stark效应射频电场测量灵敏度研究  

Sensitivity of radio-frequency electric field sensor based on Rydberg Stark effect

作　　者：韩小萱 孙光祖 郝丽萍 白素英 焦月春[4] Han Xiao-Xuan;Sun Guang-Zu;Hao Li-Ping;Bai Su-Ying;Jiao Yue-Chun(Department of Physics,Taiyuan Normal University,Jinzhong 030619,China;Department of Materials and Chemical Engineering,Taiyuan University,Taiyuan 030032,China;School of Physics and Information Engineering,Shanxi Normal University,Taiyuan 030031,China;State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Laser Spectroscopy,Shanxi University,Taiyuan 030006,China)

机构地区：[1]太原师范学院物理系,晋中030619 [2]太原学院材料与化学工程系,太原030032 [3]山西师范大学物理与信息工程学院,太原030031 [4]山西大学激光光谱研究所,量子光学与光量子器件国家重点实验室,太原030006

出　　处：《物理学报》2024年第9期88-94,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12104337,12204292,12120101004);山西省高等学校科技创新项目(批准号:2021L438,2022L268);山西省基础研究计划(批准号:202203021212018,202203021212405)资助的课题

摘　　要：里德伯原子极化率大,在外加电场作用下原子能级发生Stark分裂和频移,可实现里德伯原子高灵敏电场传感器的研究.采用Shirley的简化不含时Floquet哈密顿量模型,计算了Cs里德伯原子的AC Stark能谱,修正后与实验上测得的弱场中Cs里德伯原子的DC Stark离子能谱拟合,在获得60D_(5/2)和70D_(5/2)里德伯原子态极化率αDC的同时实现低频弱场灵敏度的计算.并计算了Cs里德伯原子60D_(5/2)态频率在0—500 GHz范围内振荡电场中的AC Stark能级频移量,对里德伯原子传感器在其宽光谱范围内的灵敏度进行定量分析,实现任意场频率最佳灵敏度的计算,为里德伯原子传感器的研究提供理论基础.Rydberg atoms hold special attraction in electric applications due to their large transition electric dipole moments and huge polarization,which leads to a strong response of atom to electric fields.In radio-frequency(RF)fields,the Rydberg levels are AC Stark shift and splitting,which can realize the study of high-sensitivity electric field sensor of Rydberg atoms.In this work,we use the simpler Shirley’s time-independent Floquet Hamiltonian model to calculate the AC Stark energy spectrum of Cs Rydberg atoms.This model can reduce the basic Hamiltonian into such a Hamiltonian that includes only those Rydberg states that have direct dipole-allowed transitions with the target state,thereby significantly improving the speed of computation.The accuracy of the calculation is proved by fitting with the calculated frequency shift of DC Stark energy levels in the weak fields,and the polarizability of 60D_(5/2) and 70D_(5/2) Rydberg atomic states are obtained by fitting with the measured ion spectra of DC Stark Cs ultra-cold Rydberg atoms in magneto-optical trap.In addition,we calculate the AC Stark shift of Cs Rydberg atom∣60D_(5/2),m_(j)=1/2>state in electric fields with different frequencies withε=100 mV/m.Rydberg atoms provide a structured spectrum of sensitivity to electric fields due to strong resonant interaction and off-resonant interaction with many dipole-allowed transitions to nearby Rydberg states.This kind of the frequency response structure is of significance to a broadband sensor.And we calculate the sensitivity and the scaling of the signal-to-noise ratio(SNR),β,varying with detuning from the∣60D_(5/2)>→∣61P3/2> transition.The value ofβallows one to use the result for any Rydberg state sensor to determine the SNR for anyΕin a 1 s measurement.Therefrom,Rydberg sensor can preferentially detect many RF frequencies spreading across its carrier spectral range without modification while effectively rejecting large portions where the atom response is significantly weaker,and the signal depends primar

关 键 词：AC STARK效应 里德伯传感器 Floquet模型 

分 类 号：O562[理学—原子与分子物理]