Phase-dependent optical bistability in the quantum dot nanostructure molecules via inter-dot tunneling

The optical bistability behavior of a probe field in the V-type pump-probe asymmetric semiconductor quantum dot (QD) nanostructure molecules are investigated in the presence of the inter-dot tunneling effect. It is shown that the optical bistability (OB) of the system in two-photon resonance condition can be controlled via amplitude or relative phase of applied fields. It is demonstrated that the optical bistability (OB) behavior of the system can be controlled by inter-dot tunneling effect and the considerable output is obtained for zero input. The optical properties of the system, beyond two-photon resonance condition, are then discussed. The inter-dot tunneling coherence in QD molecule permits the pump field to scatter into the probe field frequency. This can apply the phase-dependent behavior for the optical properties of the system. However, the optical properties of the medium in the probe field frequency, in general, are not phase-dependent. - Highlights: ► Optical bistability (OB) in QD molecules can be controlled by characteristics of applied fields. ► OB behavior in QD molecules, beyond two-photon resonance condition is not phase-dependent. ► The quantum dot size distribution can affect the optical bistability behavior of system.