Rydberg Atomic Polarization Spectroscopy Implementation And Laser Frequency Stabilization Application

Rydberg atoms have the characteristics of long life,large electric dipole moment and high polarizability,and have been widely used in quantum computing,quantum simulation and quantum precision measurement in recent years.A variety of spectroscopic techniques have been developed based on the Rydberg atom,such as the ladder-type three-level Rydberg atom’s electromagnetically induced transparency（EIT）,which uses quantum interference effects to achieve a narrow sub-Doppler spectrum in a room-temperature atomic vapor cell.Two-color polarization spectroscopy（TCPS）based on Rydberg atoms is a modulation-free spectrum that can also achieve sub-Doppler spectroscopy at room temperature atomic gas chambers,and can be extended to multi-wavelength laser frequency stabilization without modulation.The main content of this article is divided into the following sections:The first chapter provides a brief introduction to the properties of the Rydberg atom,the Rydberg atomic spectrum,and their related applications.The second chapter briefly describes the principle of polarization spectroscopy and its application in laser frequency stabilization and other fields.The third chapter describes the laser system for ¹³³Cs Rydberg atomic excitation.The realization schemes of various optical pulses at 852 nm are studied theoretically.Based on the electro-optical intensity modulator（EOIM）,the time mode of continuous optical pulses at 852 nm is regulated.The square wave pulses and e-exponential pulses at the scale of nanosecond（ns）are prepared.The implementation scheme of 509 nm laser system is theoretically studied,and the narrow linewidth 509 nm laser system is realized based on narrow linewidth laser seeder,fiber power amplification and nonlinear laser wavelength conversion technology.Based on EOIM modulation and pulse amplification technology,high-power ns-scale 509 nm pulsed light was prepared.Based on the two-photon excitation scheme of 852 nm+509 nm and the optimized pulsed optical time mode,the Rydberg state of Cesium atom was prepared.The fourth chapter introduces Rydberg atomic polarization spectroscopy and laser frequency stabilization.Based on the 6S_1/2-6P_3/2-70S_1/2 ladder-type three-level system of Cesium atom,the Rydberg state two-color polarization spectrum is realized by the 852nm and 509nm two-photon excitation.The dependence of two-color polarization spectrum on laser polarization,frequency and power of 852 nm probe laser and 509 nm coupling laser is investigated experimentally.The frequency locking of 509 nm laser system is realized by using Rydberg state two-color polarization spectrum.The innovation points are following:1)Based on the two-photon excitation of 852 nm+509 nm,the two-color polarization spectrum of the Rydberg state is realized in a Cesium atomic vapor cell at room temperature.2)The Rydberg atomic two-color polarization spectrum is used to achieve unmodulated frequency locking for 852 nm and 509 nm laser systems.This scheme can be applied to two-photon,multiphoton Rydberg state-excited unmodulated laser frequency stabilization.