Strong Coherent Light Amplification with Double Electromagnetically Induced Transparency Coherences

TL;DR

This paper reports the experimental demonstration of coherent probe field amplification in a tripod-type atomic system using double electromagnetically induced transparency, enabling near-resonant amplification via stimulated Raman scattering with suppressed absorption.

Contribution

It introduces a novel method combining double EIT and controlled population transfer to achieve efficient coherent amplification in atomic vapors.

Findings

Achieved suppression of atomic absorption at resonance.

Demonstrated near-resonant amplification via stimulated Raman scattering.

Enhanced amplification efficiency through population transfer control.

Abstract

We experimentally demonstrate coherent amplification of probe field in a tripod-type atoms driven by strong coupling, signal and weak probe fields. We suppress linear and nonlinear atomic absorptions for resonant and near resonant probe via double electromagnetically induced transparency (DEIT). Combining these advantages of suppressed absorption along with temperature- or atomic-density-controlled transfer of population(ToP) between hyperfine ground states, we can induce near-resonant amplification of probe through stimulated Raman scattering(SRS) pumped by low-intensity signal field. The increased population difference of initial and final states of SRS due to increased ToP rate, together with reduced absorption at the second EIT window in an optically thick Cesium vapor, gives rise to highly effective coherent amplification.