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

Optical phase conjugation using Raman coherent population trapping

Philip Hemmer, D. P. Katz, M. S. Shahriar, Prem Kumar, Mark Cronin‐Golomb

Published May 10, 1996• 1 citation
Publisher

Abstract

Coherent population trapping can be used to achieve efficient optical phase conjugation in a double-(Lambda) system at pump intensities well below the saturation intensity of the optical transitions. Experimental evidence for this process in sodium vapor qualitatively verifies this prediction.
DOI
10.1117/12.239482

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Recently experiments on investigation of four wave mixing in sodium vapor cell have been performed by group of Dr P. Hemmer. It has been shown in these experiments that generation of a phase-conjugate wave takes place at large detuning of a pumping wave from the resonant transition in a double Lambda system of atomic levels only (so called case of Raman interaction). Moreover, the experiments demonstrated high efficiency of such Raman interaction for generation of the conjugate wave with low intensities of the exciting waves that indicates realization of new type of Raman laser. The aim of our work is theoretical analysis and numerical simulation of the experiment on the basis of exact solution of self-consistent system of Maxwell-Bloch equations. The atom-field interaction scheme is shown in the report. A peculiarity of this scheme is that the same pumping wave interacts with both transitions 1 ---> 3 and 2 ---> 4 simultaneously.
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