Laser Physics

Behavior of optical bistability in multifold quantum dot molecules

Hamid Reza Hamedi, Mohammad Reza Mehmannavaz

Published Jan 9, 2015• 17 citations

Abstract

We analyze the optical bistability (OB) behavior in a multifold quantum dot (QD) molecule composed of five quantum dots controlled by the tunneling coupling. It is shown that the optical bistability can strongly be affected by the tunneling inter-dot coupling coefficients as well as detuning parameters. In addition, we find that the rate of an incoherent pump field has a leading role in modification of the OB threshold. We then generalize our analysis to the case of multifold quantum dot molecules where the number of the quantum dots is N (with a center dot and satellite dots). We compare the OB features that could occur in a multifold QD system consist of three ( ), four ( ), and five ( N = 5) quantum dots. We realize that the OB threshold increases as the number of satellite QDs increases. Such controllable optical bistability in multiple QD molecules may provide some new possibilities for technological applications in optoelectronics and solid-state quantum information science.

DOI: 10.1088/1054-660x/25/2/025403

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