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Polarization-Correlated Photon Pairs from a Single Quantum Dot

Charles Santori·David Fattal·Matthew Pelton·Glenn S. Solomon·Yoshihisa Yamamoto
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Abstract

Polarization correlation in a linear basis, but not entanglement, is observed between the biexciton and single-exciton photons emitted by a single InAs quantum dot in a two-photon cascade. The results are well described quantitatively by a probabilistic model that includes two decay paths for a biexciton through a non-degenerate pair of one-exciton states, with the polarization of the emitted photons depending on the decay path. The results show that spin non-degeneracy due to quantum-dot asymmetry is a significant obstacle to the realization of an entangled-photon generation device.

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Charles Santori, David Fattal, Matthew Pelton, Glenn S. Solomon, Yoshihisa Yamamoto. 2002-07-25. Polarization-Correlated Photon Pairs from a Single Quantum Dot. https://doi.org/10.1103/physrevb.66.045308

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