Large Fizeau's light-dragging effect in a moving electromagnetically induced transparent medium

TL;DR

This paper demonstrates a significantly enhanced light-dragging effect in a cold atomic ensemble, enabling highly sensitive atom-based velocimetry and advancing motional sensing technologies.

Contribution

The study achieves over three orders of magnitude enhancement of light dragging in an electromagnetically induced transparent medium, enabling a new level of velocity sensitivity.

Findings

Enhanced light dragging by at least 1000 times compared to previous experiments.

Realized an atom-based velocimeter with sensitivity 100 times higher than atomic velocity width.

Potential for motional sensing in room temperature vapors or solid materials.

Abstract

As one of the most influential experiments on the development of modern macroscopic theory from Newtonian mechanics to Einstein's special theory of relativity, the phenomenon of light dragging in a moving medium has been discussed and observed extensively in different types of systems. To have a significant dragging effect, the long duration of light travelling in the medium is preferred. Here we demonstrate a light-dragging experiment in an electromagnetically induced transparent cold atomic ensemble and enhance the dragging effect by at least three orders of magnitude compared with the previous experiments. With a large enhancement of the dragging effect, we realize an atom-based velocimeter that has a sensitivity two orders of magnitude higher than the velocity width of the atomic medium used. Such a demonstration could pave the way for motional sensing using the collective state of atoms in a room temperature vapour cell or solid state material.