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arXiv · 2207.10210

Homodyne measurement with a Schr\"odinger cat state as a local oscillator

Joshua Combes·Austin P. Lund
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Abstract

Homodyne measurements are a widely used quantum measurement. Using a coherent state of large amplitude as the local oscillator, it can be shown that the quantum homodyne measurement limits to a field quadrature measurement. In this work, we give an example of a general idea: injecting non-classical states as a local oscillator can led to non-classical measurements. Specifically we consider injecting a superposition of coherent states, a Schr\"odinger cat state, as a local oscillator. We derive the Kraus operators and the positive operator-valued measure (POVM) in this situation.

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Joshua Combes, Austin P. Lund. 2022-07-20. Homodyne measurement with a Schr\"odinger cat state as a local oscillator. https://doi.org/10.1103/physreva.106.063706

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