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Journal of Atomic Molecular and Optical Physics

The Kerr Nonlinearity in an N-Type Four-Level System via Spontaneously Generated Coherence

Yingjie Du, Kang Jin, Junxiang Zhang

Published Oct 26, 2009• 4 citations
Publisher

Abstract

The Kerr nonlinearity is investigated in an N-type four-level atomic system whose both supper levels are degenerated or nearly degenerate. It is found that the spontaneously generated coherence as a result of the degenerate levels can change the Kerr nonlinearity dramatically depending on the angle between two spontaneous channels. In addition, we discover that the probe field makes its own contribution to the nonlinearity in comparison to indifference in general three-level systems.

DOI
10.1155/2009/382764

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Abstract We study the electromagnetically induced grating in a four-level N-type atomic system in the presence of Kerr field, spontaneously generated coherence (SGC), and Doppler broadening. The transmission and diffraction intensity of the probe light is controlled through the Kerr field and the SGC. The gradual increase of the Kerr field and the SGC in the presence of a Doppler broadened medium leads to the enhanced multiple transmission and intensity peaks of the probe light. The electromagnetically induced grating may find applications in a quantized probe field, all-optical switching, routing, and light storage devices.