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arXiv · 2408.08404

Controlled-squeeze gate in superconducting quantum circuits

Nicolás F. Del Grosso·Rodrigo G. Cortiñas·Paula I. Villar·Fernando C. Lombardo·Juan Pablo Paz
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Abstract

We present a method to prepare non-classical states of the electromagnetic field in a microwave resonator. It is based on a controlled gate that applies a squeezing operation on a SQUID-terminated resonator conditioned on the state of a dispersively coupled qubit. This controlled-squeeze gate, when combined with Gaussian operations on the resonator, is universal. We explore the use of this tool to map an arbitrary qubit state into a superposition of squeezed states. In particular, we target a bosonic code with well-defined superparity which makes photon losses detectable by non-demolition parity measurements. We analyze the possibility of implementing this using state-of-the-art circuit QED tools and conclude that it is within reach of current technologies.

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Nicolás F. Del Grosso, Rodrigo G. Cortiñas, Paula I. Villar, Fernando C. Lombardo, Juan Pablo Paz. 2024-08-15. Controlled-squeeze gate in superconducting quantum circuits. https://arxiv.org/abs/2408.08404

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