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arXiv · 2504.01664

Preparation of conditionally-squeezed states in qubit-oscillator systems

Marius K. Hope·Jonas Lidal·Francesco Massel
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Abstract

Inspired by recent advances in the manipulation of superconducting circuits coupled to mechanical modes in the quantum regime, we propose a protocol for generating superpositions of orthogonally squeezed states in a quantum harmonic oscillator. The protocol relies on a quadratic coupling between the oscillator and a qubit, and is conceptually similar to methods used for preparing cat states in qubit-oscillator systems. We numerically evaluate the robustness of the state-preparation scheme in the presence of decoherence, considering environmental coupling for both the harmonic oscillator and the qubit. As a potential application, we introduce a quantum error-correcting code based on conditionally-squeezed states and analyze its error-mitigation properties.

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Marius K. Hope, Jonas Lidal, Francesco Massel. 2025-04-02. Preparation of conditionally-squeezed states in qubit-oscillator systems. https://doi.org/10.1103/jrrb-hymw

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