Coherent control of optical bistability and multistability in a triple semiconductor quantum well nanostructure

This paper deals with optical bistability (OB) and optical multistability (OM) behaviors for a triple semiconductor quantum well (SQW) structure driven coherently with two control fields, confined in a unidirectional ring cavity. The effect of different system parameters on OB and OM is explored. It is found that the threshold of onset of the OB can be controlled by manipulating the Rabi frequency of control fields. In this case, OB can be converted to OM. Then we investigate the effect of probe and control field detunings on OB behaviors. We found that the frequency detuning of probe field affects only the upper–lower branches of the OB curves but has no specific impact on OB threshold. By manipulating the first control field detuning, neither the OB threshold intensity nor upper–lower branches change. Finally, it is found that increasing the second control field detuning can reduce merely the OB threshold intensity, while no change happens in upper–lower OB branches. The results may be applicable in real experiments for realizing an all-optical switching or coding element in a solid-state platform.