Cavity-QED effects on entangled photon generation from a quantum dot

We theoretically study polarization-entangled photon generation due to the resonant hyper-parametric scattering in a single quantum dot embedded in a microcavity. In contrast to the entangled photon generation from semiconductor until now, a biexciton does not play an important role because of the characteristic excitation states in the cavity QED. Although co-polarized non-entangled photon pairs are also emitted, the rate of entangled photon pairs becomes high in the strong-coupling limit due to the photon blockade effect.