Radiative two-photon cascades from biexcitons in semiconductor quantum dots under resonant two-photon excitation are promising candidates for the generation of photon pairs. In this work, we propose a scheme to obtain two-photon emission that allows to operate under very intense driving fields. This approach relies on the Purcell enhancement of two-photon virtual transitions between states of the biexciton dressed by the laser. The richness provided by the biexcitonic level structure allows to reach a variety of regimes, from antibunched and bunched photon pairs with polarization orthogonal to the driving field, to polarization entangled two-photon emission. This evidences that the general paradigm of two-photon emission from a ladder of dressed states can find interesting, particular implementations in a variety of systems.
@article{arxiv.1506.05050,
title = {Enhanced two-photon emission from a dressed biexciton},
author = {Carlos Sánchez Muñoz and Fabrice P. Laussy and Carlos Tejedor and Elena del Valle},
journal= {arXiv preprint arXiv:1506.05050},
year = {2016}
}