Near-infrared light controlling using the photonic crystal with coupled quantum dots in defect layer

Abstract

We propose a multilayer structure with an active region consisting coupled semiconductor quantum dots to modulate a near-infrared optical probe. The vertically aligned arrays of two quantum dots are simulated to obtain the electron and hole energy eigenvalues. The inter-dot electron and hole tunneling along with coupling laser field are considered to investigate the optical properties of the quantum dot molecules via density matrix method. Probe field transmission through the designed one dimensional photonic crystal, with composed quantum dot molecules defect layer, is monitored. The necessary values of the controlling parameters, i.e. tunneling strength, coupling field intensity and its relative phase with respect to the probe signal for operating in different ON/OFF and amplified-ON regimes are determined. The dynamical response of the quantum dot molecules is also investigated to obtain the switching time between these three regimes. The obtained results confirm that the proposed structure can operate as an optical switch or amplifier in communication technology.