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arXiv · 1608.07135

Multi-photon absorption in optical gratings for matter waves

Kai Walter·Stefan Nimmrichter·Klaus Hornberger
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Abstract

We present a theory for the diffraction of large molecules or nanoparticles at a standing light wave. Such particles can act as a genuine photon absorbers due to their numerous internal degrees of freedom effecting fast internal energy conversion. Our theory incorporates the interplay of three light-induced properties: the coherent phase modulation due to the dipole interaction, a non-unitary absorption-induced amplitude modulation described as a generalized measurement, and a coherent recoil splitting that resembles a quantum random walk in steps of the photon momentum. We discuss how these effects show up in near-field and far-field interference schemes, and we confirm our effective description by a dynamic evaluation of the grating interaction, which accounts for the internal states.

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Kai Walter, Stefan Nimmrichter, Klaus Hornberger. 2016-08-25. Multi-photon absorption in optical gratings for matter waves. https://doi.org/10.1103/physreva.94.043637

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