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arXiv · 2507.15508

Amplified quantum non-demolition measurements of optical quadratures using quadratic nonlinearity

D. I. Salykina·V. S. Liamin·P. R. Sharapova·F. Ya. Khalili
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Abstract

Quantum non-demolition (QND) measurement is a special technique that allows to evade quantum back-action. In this paper, we propose a new QND measurement scheme of the optical field quadratures based on the non-degenerate optical parametric amplifier. We show that for a proper set of parameters, this scheme can realize a new type of QND measurement, where the quadrature of interest is amplified, but still does not subject to any back action.

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D. I. Salykina, V. S. Liamin, P. R. Sharapova, F. Ya. Khalili. 2025-07-21. Amplified quantum non-demolition measurements of optical quadratures using quadratic nonlinearity. https://arxiv.org/abs/2507.15508

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