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arXiv · 2105.00814

Atom interferometry with quantized light pulses

Katharina Soukup·Fabio Di Pumpo·Tobias Asano·Wolfgang P. Schleich·Enno Giese
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Abstract

The far-field patterns of atoms diffracted from a classical light field, or from a quantum one in a photon-number state are identical. On the other hand, diffraction from a field in a coherent state, which shares many properties with classical light, displays a completely different behavior. We show that in contrast to the diffraction patterns, the interference signal of an atom interferometer with light-pulse beam splitters and mirrors in intense coherent states does approach the limit of classical fields. However, low photon numbers reveal the granular structure of light, leading to a reduced visibility since Welcher-Weg (which-way) information is encoded into the field. We discuss this effect for a single photon-number state as well as a superposition of two such states.

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Katharina Soukup, Fabio Di Pumpo, Tobias Asano, Wolfgang P. Schleich, Enno Giese. 2021-05-03. Atom interferometry with quantized light pulses. https://doi.org/10.1063/5.0048806

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