Nonclassical correlation of polarization-entangled photons in a biexciton-exciton cascade

Abstract

We develop a theoretical model to study the intensity-intensity correlation of polarization-entangled photons emitted in a biexciton-exciton cascade. We calculate the degree of correlation and show how polarization correlations are affected by the presence of dephasing and energy-level splitting of the excitonic states. Our theoretical calculations are in agreement with the recent observation of polarization-dependent intensity-intensity correlations from a single semiconductor quantum dot (Stevenson et al 2006 Nature 439 179). Our model can be extended to study polarization-entangled photon emission in coupled quantum dot systems.