Theoretical study of EIT-AT nonlinearity with Cs atomic ladder four-level system

Rydberg atoms have large polarizability and microwave transition dipole moments and are very sensitive to external electromagnetic fields, which can realize high-resolution and sensitive measurements of ultra-wide-band Rabi frequency electric fields based on Rydberg atoms. Temperature has a certain effect on Rydberg atomic ensemble, and the Doppler effect caused by temperature must be considered. In this paper, we construct a ladder four-level system 6S 1/2 →6P 3/2 →52D 5/2 →53P 3/2 using 133 Cs atom gas. By numerically solving the master equation of the system, we theoretically studied the influence of the Doppler effect on the EIT-AT splitting, which was represented by parameterized D T . The results showed that the influence of temperature was mainly concentrated in the range of 0.01 K to 100 K. In addition, the influence of the probe laser and coupling laser Rabi frequencies on the EIT-AT splitting was studied at specific temperatures. These results help us deepen our understanding of the Doppler effect and have certain guiding significance for the optimization of experimental parameters.