arXiv:1509.08951 · Journal of Modern Optics

Suppression of the four-wave mixing amplification via Raman absorption

G. Romanov, Chris O’Brien, Irina V. Novikova

Published Jan 22, 2016• 13 citations

Abstract

We propose a method to controllably suppress the effect of the four-wave mixing caused by the coupling of the strong control optical field to both optical transitions in the Λ system under the conditions of electromagnetically induced transparency (EIT). At sufficiently high atomic density, this process leads to amplification of a weak optical signal field, that is detrimental for the fidelity of any EIT-based quantum information applications. Here we show that an additional absorption resonance centred around the Stokes field frequency, generated in such a four-wave mixing process, may efficiently suppress the unwanted probe amplification without affecting properties of the EIT interaction. We discuss the possibility of creating such tunable absorption using two-photon Raman absorption resonances in the other Rb isotope, and present some preliminary experimental results.

DOI: 10.1080/09500340.2015.1133856

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