Realization of all-optical switch and diode via Raman gain process using a Kerr field

Abstract

The idea of optical photonic crystal, which is generated using two counter-propagating fields, is revisited to study gain-assisted all-optical switch and diode using Kerr field. Two counter-propagating fields with relative detuning generate standing-wave field pattern which interacts with a four-level atomic system. The standing-wave field pattern acts like a static photonic crystal for , however, it behaves as a moving photonic crystal for . The reflection and transmission coefficients are calculated for the case when a weak incident probe pulse propagates through the system. For static photonic crystal, the system acts like an all optical transistor—as a switch—via control of the external Kerr field, such that, when the Kerr field is off (on) the switch is ON (OFF). However, for a moving photonic crystal, the system acts as an all-optical diode via control of the external Kerr field. The advantage of using the gain-assisted model is the fact that the transmission efficiency is high, i.e. almost .