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arXiv · 2507.21548

Quantum-Classical Boundary Engineering in Weak-to-Strong Measurements via Squeezed Vacua

Janarbek Yuanbek·Wen-Long Ma·Yusuf Turek
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Abstract

This study establishes a post-selected von Neumann framework to regulate non-classical features of single-photon-subtracted squeezed vacuum (SPSSV) and two-mode squeezed vacuum (TMSV) states during weak-to-strong measurement transitions. By synergizing Wigner-Yanase skew information, Amplitude Squared (AS) squeezing, sum squeezing, and photon statistics, we demonstrate weak value amplification as a unified control mechanism for quantum properties. Phase-space analysis via the Husimi Kano Q function reveals a critical transition: as coupling strength increases, SPSSV and TMSV states evolve from quantum non-Gaussianity to classical single-peak separability, marking a quantum-classical boundary crossing. This critical point is validated as the optimal threshold for noise suppression and signal enhancement in quantum metrology. The work provides a tunable platform for quantum sensing and weak-signal detection technologies.

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Janarbek Yuanbek, Wen-Long Ma, Yusuf Turek. 2025-07-29. Quantum-Classical Boundary Engineering in Weak-to-Strong Measurements via Squeezed Vacua. https://arxiv.org/abs/2507.21548

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