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arXiv · 2507.12288

Ultra-strong Quantum Squeezing Mediated by Plasma Waves

Kenan Qu·Nathaniel J. Fisch
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Abstract

Quantum squeezed states enable precision measurements beyond the standard quantum limit, but conventional solid-state media fundamentally limit pump intensities to the ionization threshold. We demonstrate that plasma waves can mediate ultra-strong two-mode squeezing through stimulated Raman scattering, achieving up to ultrastrong squeezing using $10^{16}{Wcm^{-2}}$ pump lasers. Employing two copropagating pump beams with frequency difference matching twice the plasma frequency, we generate quantum-correlated photon pairs through phonon-mediated four-wave mixing. The process exhibits remarkable thermal noise tolerance, allowing strong squeezing even with large thermal phonon numbers. This plasma-based approach produces squeezed states with ultrahigh photon numbers, opening new possibilities for strong-field applications across optical to X-ray wavelengths.

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Kenan Qu, Nathaniel J. Fisch. 2025-07-16. Ultra-strong Quantum Squeezing Mediated by Plasma Waves. https://arxiv.org/abs/2507.12288

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