High-contrast double Bragg interferometry via detuning control

TL;DR

This paper introduces a novel detuning control scheme for double Bragg diffraction in atom interferometers, significantly enhancing contrast and robustness for precision measurements.

Contribution

It presents a hybrid detuning sweep and optimal control approach to improve interferometer contrast under external acceleration.

Findings

OCT strategy maintains >95% contrast under realistic conditions.

DS-DBD achieves >90% contrast with well-collimated BECs.

Hybrid protocol offers practical high-contrast interferometry.

Abstract

We propose high-contrast Mach-Zehnder atom interferometers based on double Bragg diffraction (DBD) operating under external acceleration. To mitigate differential Doppler shifts and experimental imperfections, we introduce a tri-frequency laser scheme with dynamic detuning control. We evaluate four detuning-control strategies-conventional DBD, constant detuning, linear detuning sweep (DS-DBD), and a hybrid protocol combining detuning sweep with optimal control theory (OCT)-using exact numerical simulations and a five-level S-matrix model. The OCT strategy provides the highest robustness, maintaining contrast above 95\% under realistic conditions, while the DS-DBD strategy sustains contrast above 90\% for well-collimated Bose-Einstein condensates. These results offer practical pathways to high-contrast, large-momentum-transfer DBD-based interferometers for precision quantum sensing and fundamental physics tests.