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arXiv · 1808.03355

Atom Interferometry with Top-Hat Laser Beams

N. Mielec·M. Altorio·R. Sapam·D. Horville·D. Holleville·L. A. Sidorenkov·A. Landragin·R. Geiger
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Abstract

The uniformity of the intensity and phase of laser beams is crucial to high-performance atom interferometers. Inhomogeneities in the laser intensity profile cause contrast reductions and systematic effects in interferometers operated with atom sources at micro-Kelvin temperatures, and detrimental diffraction phase shifts in interferometers using large momentum transfer beam splitters. We report on the implementation of a so-called top-hat laser beam in a long-interrogation-time cold-atom interferometer to overcome the issue of the inhomogeneous laser intensity encountered when using Gaussian laser beams. We characterize the intensity and relative phase profiles of the top-hat beam and demonstrate its gain in atom-optics efficiency over a Gaussian beam, in agreement with numerical simulations. We discuss the application of top-hat beams to improve the performance of different architectures of atom interferometers.

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physics.atom-phphysics.ins-detphysics.opticsquant-ph

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N. Mielec, M. Altorio, R. Sapam, D. Horville, D. Holleville, L. A. Sidorenkov, A. Landragin, R. Geiger. 2018-08-09. Atom Interferometry with Top-Hat Laser Beams. https://doi.org/10.1063/1.5051663

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