Atom interferometry in an optical cavity

TL;DR

This paper introduces a novel atom interferometry scheme using optical cavities for enhanced control and sensitivity, demonstrating high-contrast fringes and gravity measurement with cesium atoms in a compact setup.

Contribution

The paper presents a new cavity-based atom interferometry method enabling low power, large momentum transfer, and self-aligned geometries, advancing compact high-sensitivity measurements.

Findings

Achieved >75% contrast in Ramsey-Raman fringes

Measured gravity with 60 μg/√Hz resolution

Trapped atoms in higher transverse cavity modes

Abstract

We propose and demonstrate a new scheme for atom interferometry, using light pulses inside an optical cavity as matter wave beamsplitters. The cavity provides power enhancement, spatial filtering, and a precise beam geometry, enabling new techniques such as low power beamsplitters ($<100 \mathrm{\mu W}$), large momentum transfer beamsplitters with modest power, or new self-aligned interferometer geometries utilizing the transverse modes of the optical cavity. As a first demonstration, we obtain Ramsey-Raman fringes with $>75\%$ contrast and measure the acceleration due to gravity, $\mathit{g}$, to $60 \mathrm{\mu \mathit{g} / \sqrt{Hz}}$ resolution in a Mach-Zehnder geometry. We use $>10^7$ cesium atoms in the compact mode volume ($600 \mathrm{\mu m}$ $1/e^2$ waist) of the cavity and show trapping of atoms in higher transverse modes. This work paves the way toward compact, high sensitivity, multi-axis interferometry.