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arXiv · 2507.02201

Photon number projective measurement in Schr\"odinger cat quantum state preparation procedure after parametric down-conversion interaction

V. L. Gorshenin
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Abstract

Schr\"odinger-cat (SC) states are an important resource for continuous-variable quantum computing and quantum metrology. In our previous work [JOSA B, 42, 2 (2025)], we proposed a probabilistic protocol for generating bright squeezed SC states via degenerate spontaneous parametric down-conversion (SPDC) with pump depletion, followed by projective measurement of the pump mode. In the present work, we formulate a general theoretical description of SPDC with pump depletion, introduce an efficient numerical method for computing its dynamics, and develop a practical version of the protocol proposed in [JOSA B, 42, 2 (2025)].

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V. L. Gorshenin. 2025-07-02. Photon number projective measurement in Schr\"odinger cat quantum state preparation procedure after parametric down-conversion interaction. https://arxiv.org/abs/2507.02201

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