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IEEE International Conference on Quantum Computing and Engineering (QCE)

Nonclassical Light Generation in Quantum Dot Microlasers: Toward Integrated Quantum Photonic Sources

Sahil D. Patel, Frédéric Grillot, Weng W. Chow, Sean Doan, Chen Shang, John Edward Bowers, Galan Moody

Published Aug 30, 2025• 0 citations
Publisher

Abstract

We numerically investigate the generation of nonclassical light in semiconductor micropillar cavities containing quantum dots (QDs), focusing on quadrature squeezing. Using cavity-QED, equations of motion are derived for an inhomogeneously broadened QD distribution that is incoherently excited and subjected to an injected seed laser field. Steady-state solutions are obtained and used to determine the quadrature variances. We identify a narrow parameter regime below the lasing threshold where squeezing emerges in the amplitude quadrature, with variances falling below the vacuum limit.

DOI
10.1109/qce65121.2025.00160

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We numerically investigate the generation of nonclassical light in semiconductor micropillar cavities containing quantum dots (QDs), focusing on quadrature squeezing. Using cavity-QED, equations of motion are derived for an inhomogeneously broadened QD distribution that is incoherently excited and subjected to an injected seed laser field. Steady-state solutions are obtained and used to determine the quadrature variances. We identify a narrow parameter regime below the lasing threshold where squeezing emerges in the amplitude quadrature, with variances falling below the vacuum limit.
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We introduce a method for the conditional generation of nonclassical states of light in a cavity. We consider two-level atoms traveling along the transverse direction to the cavity axis and show that by conditioning on one of the output measurements nonclassical field states are generated. The two-level atoms are prepared in the ground state and we conditioned them on the events in which they are also detected in the ground state. Nonclassical properties of the cavity mode are identified and characterized. This includes quadrature squeezing, sub-Poissonian photon-number distributions, and negative Wigner functions. We determine the optimal parameter regions where the corresponding nonclassical features are most distinct.
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