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arXiv · 1506.05050

Enhanced two-photon emission from a dressed biexciton

Carlos Sánchez Muñoz·Fabrice P. Laussy·Carlos Tejedor·Elena del Valle
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Abstract

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.

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Carlos Sánchez Muñoz, Fabrice P. Laussy, Carlos Tejedor, Elena del Valle. 2015-06-16. Enhanced two-photon emission from a dressed biexciton. https://doi.org/10.1088/1367-2630/17/12/123021

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