Propagation of coupled dark-state polaritons and storage of light in a tripod medium

TL;DR

This paper studies slow light propagation in a tripod atomic medium, revealing unique dynamics due to coupled dark-state polaritons, enabling near-perfect conversion of photons into spin excitations even for long pulses.

Contribution

It introduces a novel analysis of dark-state polariton propagation in a tripod medium, demonstrating highly efficient photon-to-spin conversion surpassing Lambda-medium capabilities.

Findings

Propagation dynamics differ significantly from Lambda-medium.

Near-unity conversion efficiency for long signal pulses.

Efficient light storage in a tripod atomic configuration.

Abstract

We consider the slow light propagation in an atomic medium with a tripod level scheme. We show that the coexistence of two types of dark-state polaritons leads to the propagation dynamics, which is qualitatively different from that in a $\Lambda $-medium, and allows therefore for very efficient conversion of signal photons into spin excitations. This efficiency is shown to be very close to 1 even for very long signal light pulses, which could not be entirely compressed into a Lambda-medium at a comparable strength of the control field.