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  • Letter
  • Open Access

Preparation of conditionally squeezed states in qubit-oscillator systems

Marius K. Hope1,2,*, Jonas Lidal1, and Francesco Massel2

  • *Contact author: maho@usn.no
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Phys. Rev. Research 8, L012046 – Published 26 February, 2026

DOI: https://doi.org/10.1103/jrrb-hymw

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 consider a quantum error-correcting code based on conditionally squeezed states and analyze its error correction properties.

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Phys. Rev. Research 8, L012046– Published 26 February, 2026
  • Received 9 April 2025
  • Accepted 21 January 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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