Sagnac interferometry based on ultra-slow polaritons in cold atomic vapors

TL;DR

This paper demonstrates how ultra-slow light in cold atomic vapors can enhance Sagnac interferometry by generating matter-wave components, leading to increased rotational sensitivity with less cooling.

Contribution

It introduces a method to combine light and matter-wave Sagnac interferometers using ultra-slow light in cold atomic gases, enhancing rotational sensitivity.

Findings

Matter-wave sensitivity can be achieved in large-area interferometers.

Enhanced Sagnac phase shift observed with less cooling.

Potential for high rotational sensitivity in compact setups.

Abstract

The advantages of light and matter-wave Sagnac interferometers -- large area on one hand and high rotational sensitivity per unit area on the other -- can be combined utilizing ultra-slow light in cold atomic gases. While a group-velocity reduction alone does not affect the Sagnac phase shift, the associated momentum transfer from light to atoms generates a coherent matter-wave component which gives rise to a substantially enhanced rotational signal. It is shown that matter-wave sensitivity in a large-area interferometer can be achieved if an optically dense vapor at sub-recoil temperatures is used. Already a noticeable enhancement of the Sagnac phase shift is possible however with much less cooling requirements.