Why momentum width matters for atom interferometry with Bragg pulses

TL;DR

This paper analyzes how the momentum width of atomic sources limits the efficiency and phase sensitivity of Bragg pulse atom interferometers, providing quantitative insights for optimizing large momentum transfer devices.

Contribution

It introduces a theoretical framework to quantify the impact of atomic momentum width on Bragg mirror efficiency and interferometer sensitivity, aiding in the design of advanced atom interferometry systems.

Findings

Momentum width sets a fundamental limit on transfer efficiency.

Phase sensitivity is constrained by atomic source momentum distribution.

Optimization methods improve design of Bragg pulses for inertial sensing.

Abstract

We theoretically consider the effect of the atomic source's momentum width on the efficiency of Bragg mirrors and beamsplitters and, more generally, on the phase sensitivity of Bragg pulse atom interferometers. By numerical optimization, we show that an atomic cloud's momentum width places a fundamental upper bound on the maximum transfer efficiency of a Bragg mirror pulse, and furthermore limits the phase sensitivity of a Bragg pulse atom interferometer. We quantify these momentum width effects, and precisely compute how mirror efficiencies and interferometer phase sensitivities vary as functions of Bragg order and source type. Our results and methodology allow for an efficient optimization of Bragg pulses and the comparison of different atomic sources, and will help in the design of large momentum transfer Bragg mirrors and beamsplitters for use in atom-based inertial sensors.