Optimized Raman pulses for atom interferometry

TL;DR

This paper develops and experimentally demonstrates optimized Raman pulse sequences that significantly enhance the fidelity and robustness of atom interferometry, especially in inhomogeneous and non-ideal conditions.

Contribution

It introduces novel pulse designs that improve transfer efficiency and robustness in atom interferometry, outperforming conventional pulses in thermal atom samples.

Findings

Achieved 99.8% ground state transfer efficiency with optimized pulses.

Enhanced fringe visibility threefold in inhomogeneous samples.

Maintained high efficiency at detunings where conventional pulses fail.

Abstract

We present mirror and beamsplitter pulse designs that improve the fidelity of atom interferometry and increase its tolerance of systematic inhomogeneities. These designs are demonstrated experimentally with a cold thermal sample of $^{85}$Rb atoms. We first show a stimulated Raman inversion pulse design that achieves a ground hyperfine state transfer efficiency of 99.8(3)%, compared with a conventional $\pi$ pulse efficiency of 75(3)%. This inversion pulse is robust to variations in laser intensity and detuning, maintaining a transfer efficiency of 90% at detunings for which the $\pi$ pulse fidelity is below 20%, and is thus suitable for large momentum transfer interferometers using thermal atoms or operating in non-ideal environments. We then extend our optimization to all components of a Mach-Zehnder atom interferometer sequence and show that with a highly inhomogeneous atomic sample the fringe visibility is increased threefold over that using conventional $\pi$ and $\pi/2$ pulses.