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arXiv · 2212.07087

Signatures of the Optical Stark Effect on Entangled Photon Pairs from Resonantly-Pumped Quantum Dots

Francesco Basso Basset·Michele B. Rota·Mattia Beccaceci·Tobias M. Krieger·Quirin Buchinger·Julia Neuwirth·Hêlio Huet·Sandra Stroj·Saimon F. Covre da Silva·Giuseppe Ronco·Christian Schimpf·Sven Höfling·Tobias Huber-Loyola·Armando Rastelli·Rinaldo Trotta
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Abstract

Two-photon resonant excitation of the biexciton-exciton cascade in a quantum dot generates highly polarization-entangled photon pairs in a near-deterministic way. However, the ultimate level of achievable entanglement is still debated. Here, we observe the impact of the laser-induced AC-Stark effect on the quantum dot emission spectra and on entanglement. For increasing pulse-duration/lifetime ratios and pump powers, decreasing values of concurrence are recorded. Nonetheless, additional contributions are still required to fully account for the observed below-unity concurrence.

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Francesco Basso Basset, Michele B. Rota, Mattia Beccaceci, Tobias M. Krieger, Quirin Buchinger, Julia Neuwirth, Hêlio Huet, Sandra Stroj, Saimon F. Covre da Silva, Giuseppe Ronco, Christian Schimpf, Sven Höfling, Tobias Huber-Loyola, Armando Rastelli, Rinaldo Trotta. 2022-12-14. Signatures of the Optical Stark Effect on Entangled Photon Pairs from Resonantly-Pumped Quantum Dots. https://doi.org/10.1103/physrevlett.131.166901

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