Optimal Control Design of Robust Raman Pulses for High-Fidelity Cold-Atom Interferometry

Abstract

The performance of high-precision cold-atom interferometers is often limited by imperfections in the Raman laser fields. We present a reproducible framework for robust Raman mirror-pulse design and compare Krotov, GRAPE, and CRAB under a common normalized peak-amplitude limit of 3.0. The effective two-level model uses a 25-member detuning--amplitude ensemble and a dense out-of-sample grid. In the fixed-budget study, GRAPE attained a terminal ensemble error of $1.224\times 10^{-2}$ and projected Krotov attained $1.243\times 10^{-2}$; Krotov occupied a slightly larger $P_e\ge 0.9$ grid fraction (0.177 versus 0.170). The best of five CRAB seeds gave $3.081\times 10^{-2}$. In the interferometer calculation, GRAPE produced the largest contrast, $0.582\pm 0.019$, while Krotov and the selected CRAB pulse gave $0.454\pm 0.019$ and $0.439\pm 0.023$, respectively. These results establish a reproducible comparison of trade-offs, rather than universal superiority of any one optimizer.