Diffraction phase-free Bragg atom interferometry

TL;DR

This paper applies optimal control theory to minimize diffraction phase shifts in high-order Bragg atom interferometers, significantly reducing systematic errors and improving measurement accuracy.

Contribution

It introduces a novel OCT-based method to control diffraction phases, enhancing the precision of atom interferometers under realistic experimental conditions.

Findings

Minimized diffraction phase below microradian level for 1% photon recoil

Mitigated systematic diffraction phase effects in high-order Bragg interferometers

Applicable to realistic finite-temperature wavepackets in Mach-Zehnder configurations

Abstract

Bragg Diffraction of matter waves is an established technique used in the most accurate quantum sensors. It is also the method of choice to operate large-momentum-transfer, high-sensitivity atom interferometers. It suffers, however, from an intrinsic multi-path character. Optimal control theory (OCT) has recently led to an improved robustness of atom interferometers to a range of challenging environmental effects such as vibrations or platform accelerations. In this theoretical work, we apply OCT protocols to control the Bragg diffraction phase shifts thereby enhancing the metrological accuracy of the interferometer. We show a minimization of the diffraction phase for realistic conditions of finite temperature of the incoming wavepacket in a multi-path, high-order Bragg interferometer in a Mach-Zehnder configuration. We study input states with different momentum widths and find that our approach mitigates diffraction phases below the microradian level in the case of $1\%$ of the photon recoil, thereby eliminating one of the leading systematic effects in atom interferometry.