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Conference on Lasers and Electro-Optics

Towards single time-bin entangled photons using quantum dots

Christophe Couteau, Gregor Weihs

Published May 1, 2008• 0 citations
Publisher

Abstract

We present our results on fluorescence and photon statistics of quantum dots. We show evidence for photon antibunching and cross-correlation measurements within the biexciton-exciton cascade using a new set-up. We also discuss directions towards a demonstration of time-bin entangled photons from a single dot.
DOI
10.1109/cleo.2008.4551795

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Resonant excitation of the biexciton state in an InAsP quantum dot by a phase-coherent pair of picosecond pulses allows preparing time-bin entangled pairs of photons via the biexciton–exciton cascade. We show that this scheme can be implemented for a dot embedded in an InP nanowire. The underlying physical mechanisms can be represented and quantitatively analyzed by an effective three-level open system master equation. Simulation parameters including decay and intensity dependent dephasing rates are extracted from experimental data, which in turn let us predict the resulting entanglement and optimal operating conditions.
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