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arXiv · 2102.13530

Parity-Swap State Comparison Amplifier for Schr\"odinger Cat States

Gioan Tatsi·Luca Mazzarella·John Jeffers
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Abstract

We propose a postselecting parity-swap amplifier for Schr\"odinger cat states that does not require the amplified state to be known a priori. The device is based on a previously-implemented state comparison amplifier for coherent states. It consumes only Gaussian resource states, which provides an advantage over some cat state amplifiers. It requires simple Geiger-mode photodetectors and works with high fidelity and approximately twofold gain.

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Gioan Tatsi, Luca Mazzarella, John Jeffers. 2021-02-26. Parity-Swap State Comparison Amplifier for Schr\"odinger Cat States. https://doi.org/10.1103/physreva.103.023709

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