Complex frequency-dependent quadrature squeezing in semiconductor lasers

Daniele Nello; Giuseppe Patera; Lorenzo Columbo

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arXiv · 2606.26266

Complex frequency-dependent quadrature squeezing in semiconductor lasers

Daniele Nello·Giuseppe Patera·Lorenzo Columbo

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Abstract

We present a comprehensive study of quadrature squeezing in a quantum well laser based on a fully quantum Langevin approach. We compute the frequency-resolved squeezing map of the laser field and identify optimal squeezing curves, revealing, for the first time to our knowledge, both frequency-dependent squeezing and complex or hidden squeezing in a semiconductor laser. We further analyse the role of the linewidth enhancement factor (alpha factor) in the emergence of these features. Our results establish semiconductor lasers as a platform for the generation of non-classical light and open new perspectives for their application in quantum communication and sensing.

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Daniele Nello, Giuseppe Patera, Lorenzo Columbo. 2026-06-24. Complex frequency-dependent quadrature squeezing in semiconductor lasers. https://arxiv.org/abs/2606.26266

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