Efficient generation of maximally entangled states via four-wave mixing in a semiconductor quantum-dot nanostructure

We investigate the generation of the maximally entangled state of two weak-light pulses (the probe and generated pulses) via four-wave mixing (FWM) in a semiconductor quantum dot (SQD) with a biexciton-exciton cascade configuration. The results show that this maximally entangled state can propagate with an ultraslow group velocity under suitable parameter conditions. For application, our proposed scheme is probably achievable with the present technology by applying the standard GaAs/InGaAs self-assemble quantum dots (QDs). Furthermore, our calculations provide a guideline for the realization of the maximally entangled state in the SQD solid-state system, which can be much more practical than that in an atomic system because of its flexible design and the wide tunable parameters.