Measurement of magic-wavelength optical dipole trap by using the laser-induced fluorescence spectra of trapped single cesium atoms

TL;DR

This paper experimentally measures the magic wavelength for a cesium optical dipole trap using laser-induced fluorescence spectra, demonstrating minimal differential light shifts at 937.7 nm for precise atomic control.

Contribution

The study identifies and characterizes the magic wavelength for cesium atoms in a linearly-polarized optical dipole trap, combining theoretical calculations with experimental validation.

Findings

Magic wavelength is 937.7 nm with minimal differential light shift.

Differential light shift is less than 0.7 MHz, under 1.2% of trap depth.

Influence of trap depth and magnetic field on measurements discussed.

Abstract

Based on the multi-level model, we have calculated light shifts for Zeeman states of hyperfine levels of cesium (Cs) 6S1/2 ground state and 6P3/2 excited state.The magic-wavelength linearly-polarized optical dipole trap (ODT) for Cs 6S1/2 F=4, mF=+4 - 6P3/2 F'=5, mF=+5 transition is experimentally constructed and characterized by using the laser-induced fluorescence spectra of trapped single Cs atoms. The magic wavelength is 937.7 nm which produces almost the same light shift for 6S1/2 F=4, mF=+4 ground state and 6P3/2 F'=5, mF=+5 excited state with linearly-polarized ODT laser beam. Compared to undisturbed Cs 6S1/2 F=4, mF=+4 - 6P3/2 F'=5, mF=+5 transition frequency in free space, the differential light shift is less than 0.7 MHz in a linearly-polarized 937.7 nm ODT, which is less than 1.2% of the trap depth. We also discussed influence of the trap depth and the bias magnetic field on the measurement results.