Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Quantum interference in light scattering and propagation

Jörg Evers, Mohammad Mahmoudi, Mihai Macovei

Published Jun 7, 2007• 0 citations

Abstract

Light scattered by a regular structure of atoms exhibits spatial interference signatures, similar to Young's classical double-slit experiment. The first-order interferences, however, are known to vanish for strong light intensities, where the incoherently fluctuating part of the emitted light dominates. Here, we show how to overcome these limitations to quantum interference in stronger laser fields, and how to recover the first-order interference in strong fields by a tailored electromagnetic vacuum with a suitable frequency dependence. We also discuss higher-order correlation functions of the scattered light, with applications, e.g., to lithography. In the second part, we study light propagation of a probe field pulse in closed-loop atomic systems. The closed interaction loop induces a sensitivity to the relative driving field phase, but in general prohibits a stationary steady state. In particular, the finite frequency width of the short probe pulse requires a time-dependent analysis beyond the so-called multiphoton resonance assumption. Using a Floquet decomposition, we identify the different contributions to the medium response, and demonstrate sub- and superluminal light propagation with small absorption or even gain, where a coupling field Rabi frequency allows to switch between sub- and superluminal light propagation.

DOI: 10.1117/12.724343

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