Applied Optics

Colossal Kerr nonlinearity based on electromagnetically induced transparency in a five-level double-ladder atomic system

Hamid Reza Hamedi, Ali Hamrah Gharamaleki, Mostafa Sahrai

Published Jul 21, 2016• 31 citations

Abstract

The paper is aimed at modeling the enhanced Kerr nonlinearity in a five-level double-ladder-type atomic system based on electromagnetically induced transparency (EIT) by using the semi-classical density matrix method. We present an analytical model to explain the origin of Kerr nonlinearity enhancement. The scheme also results in a several orders of magnitude increase in the Kerr nonlinearity in comparison with the well-known four- and three-level atomic systems. In addition to the steady-state case, the time-dependent Kerr nonlinearity and the switching feature of EIT-based colossal Kerr nonlinearity is investigated for the proposed system.

DOI: 10.1364/ao.55.005892

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The Research of Electromagnetically induced transparency and giant Kerr nonlinearity in a four-level Y-type atomic system

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