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arXiv · 2601.09431

A measurement-based protocol for the generation of delocalised quantum states of a mechanical system

Matteo Bordin
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Abstract

Non-Gaussian mechanical states are a key resource for quantum-enhanced sensing and tests of macroscopic quantum physics. We propose a measurement-based protocol to herald delocalized, nonclassical states of a mechanical oscillator in cavity optomechanics by conditioning on Geiger photodetection of the optical output. We analyse under which conditions Stokes-induced optomechanical entanglement give rise to mechanical Wigner Function negativity upon detection. We develop and compare a blue-detuned pulsed scheme and a continuous-wave steady-state scheme employing temporal-mode filtering, and we quantify heralding rates and robustness to finite temperature under realistic detection efficiencies.

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Matteo Bordin. 2026-01-14. A measurement-based protocol for the generation of delocalised quantum states of a mechanical system. https://arxiv.org/abs/2601.09431

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