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Fast initialization of Bell states with Schrödinger cats in multimode systems

Miriam Resch1,*, Ciprian Padurariu1, Björn Kubala1,2, and Joachim Ankerhold1

  • *Contact author: miriam.resch@uni-ulm.de
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Phys. Rev. Research 8, 013218 – Published 26 February, 2026

DOI: https://doi.org/10.1103/55bj-gmdv

Abstract

Schrödinger cat states play an important role for applications in continuous variable quantum information technologies. As macroscopic superpositions, they are inherently protected against certain types of noise making cat qubits a promising candidate for quantum computing. It has been shown recently that cat states occur naturally in driven Kerr parametric oscillators as degenerate ground states with even and odd parity that are adiabatically connected to the respective lowest two Fock states by switching off the drive. To perform operations with several cat qubits, one crucial task is to create entanglement between them. Here, we demonstrate efficient transformations of multimode cat states through adiabatic and diabatic switching between Kerr-type Hamiltonians with degenerate ground-state manifolds. These transformations can be used to directly initialize the cats as entangled Bell states in contrast to initializing them from entangled Fock states.

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References (29)

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Phys. Rev. Research 8, 013218– Published 26 February, 2026
  • Received 26 September 2025
  • Accepted 2 February 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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