Observation of recoil-induced resonances and electromagnetically induced absorption of cold atoms in diffuse light

TL;DR

This study experimentally observes recoil-induced resonances and electromagnetically induced absorption in cold rubidium atoms using diffuse light for both cooling and probing, revealing differences from traditional cooling methods.

Contribution

It demonstrates the occurrence of RIR and EIA in a diffuse-light cooling system and analyzes their mechanisms and spectral differences from other trapping methods.

Findings

RIR and EIA signals vary with laser detuning

Cold atom temperature depends on detuning

Spectral differences observed compared to optical molasses and MOT

Abstract

In this paper we report an experiment on the observation of the recoil-induced resonances (RIR) and electromagnetically induced absorption (EIA) of cold Rb87 atoms in diffuse light. The pump light of the RIR and the EIA comes from the diffuse light in an integrating sphere, which also serves the cooling light. The probe light beam is a weak laser split from the cooling laser in order to keep the cooling and probe lasers correlated. We measured the RIR and the EIA signal varying with the detuning of the diffuse laser light, and also measured the temperature of the cold atoms at the different detunings. The mechanism of RIR and EIA in the configuration with diffuse-light pumping and laser probing is discussed, and the difference of nonlinear spectra of cold atoms between in diffuse-light cooling system and in optical molasses as well as in a magneto-optical trap (MOT) are studied.