Enhanced two-photon emission from a dressed biexciton

TL;DR

This paper proposes a scheme to enhance two-photon emission from biexcitons in quantum dots using Purcell enhancement, enabling operation under intense driving fields and producing various photon pair regimes.

Contribution

It introduces a novel method leveraging dressed biexciton states and Purcell enhancement to improve two-photon emission in quantum dots under strong excitation.

Findings

Achieved enhanced two-photon emission with different photon regimes.

Demonstrated polarization entangled two-photon emission.

Showed the scheme's applicability to various systems.

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.