Enhancing strontium clock atom interferometry using quantum optimal control

TL;DR

This paper develops quantum optimal control pulses for strontium clock atom interferometry, enhancing robustness and fidelity, which could enable larger momentum transfer and improve detection capabilities for dark matter and gravitational waves.

Contribution

It introduces QOC pulse designs tailored for strontium clock interferometry, addressing unique quantum dynamics and demonstrating improved robustness over basic pulses.

Findings

QOC pulses outperform primitive and composite pulses in robustness

Enhanced control fidelity enables larger momentum transfer in Sr interferometers

Potential to improve dark matter and gravitational wave detection sensitivity

Abstract

Strontium clock atom interferometry is a promising new technique, with multiple experiments under development to explore its potential for dark matter and gravitational wave detection. In these detectors, large momentum transfer (LMT) using sequences of many laser pulses is necessary, and thus high fidelity of each pulse is important since small infidelities become magnified. Quantum Optimal Control (QOC) is a framework for developing control pulse waveforms that achieve high fidelity and are robust against experimental imperfections. Resonant single-photon transitions using the narrow clock transition of strontium involve significantly different quantum dynamics than more established atom interferometry methods based on far-detuned two-photon Raman or Bragg transitions, which leads to new opportunities and challenges when applying QOC. Here, we study QOC pulses for strontium clock interferometry and demonstrate their advantage over basic square pulses (primitive pulses) and composite pulses in terms of robustness against multiple noise channels. This could improve the scale of large momentum transfer in Sr clock interferometers, paving the way to achieve these scientific goals.