Optics Express

Quantum frequency translation by four-wave mixing in a fiber: low-conversion regime

Lasse Mejling, Colin J. McKinstrie, Michael G. Raymer, Karsten K. Rottwitt

Published Mar 26, 2012• 28 citations

Abstract

In this paper we consider frequency translation enabled by Bragg scattering, a four-wave mixing process. First we introduce the theoretical background of the Green function formalism and the Schmidt decomposition. Next the Green functions for the low-conversion regime are derived perturbatively in the frequency domain, using the methods developed for three-wave mixing, then transformed to the time domain. These results are also derived and verified using an alternative time-domain method, the results of which are more general. For the first time we include the effects of convecting pumps, a more realistic assumption, and show that separability and arbitrary reshaping is possible. This is confirmed numerically for Gaussian pumps as well as higher-order Hermite-Gaussian pumps.

DOI: 10.1364/oe.20.008367

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