Signatures of the optical Stark effect on entangled photon pairs from resonantly pumped quantum dots
Published in Physical Review Letters, 2023
Recommended citation: F. Basso Basset, M. B. Rota, M. Beccaceci, T. M. Krieger, Q. Buchinger, J. Neuwirth, H. Huet, S. Stroj, S. F. Covre da Silva, G. Ronco, C. Schimpf, S. Höfling, T. Huber-Loyola, A. Rastelli, R. Trotta, Phys. Rev. Lett. 131, 166901 (2023) https://doi.org/10.1103/PhysRevLett.131.166901
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-to-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.