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arXiv · 2605.21643

Balancing Quasi-Bragg Regime and Velocity Selectivity in Quantum-Enhanced Atom Interferometry

Christian Miguel Karres·Daniel Derr·Enno Giese
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Abstract

Spin squeezing in atomic ensembles enables atom interferometry with sensitivities below the shot-noise limit, but the associated entanglement is highly susceptible to loss, making imperfections in atom optics a central limitation. Bragg diffraction is an established technique for driving transitions between atomic momentum states and enables large-momentum transfer through higher-order diffraction while preserving the internal state. However, it is intrinsically limited by two competing mechanisms: Short light pulses induce parasitic diffraction into off-resonant orders beyond an effective two-level description, while long pulses face velocity selectivity. We derive analytical expressions in a second-quantized framework for the atom optics and phase uncertainty of a Mach-Zehnder interferometer including these effects. We demonstrate that sub-shot-noise scaling is achieved only in a regime of intermediate pulse duration. Furthermore, we show that deleterious effects of higher-order diffraction are partially mitigated by optimizing the input quantum state.

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Christian Miguel Karres, Daniel Derr, Enno Giese. 2026-05-20. Balancing Quasi-Bragg Regime and Velocity Selectivity in Quantum-Enhanced Atom Interferometry. https://doi.org/10.1103/wr69-9hr5

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