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Optimizing decoherence in the generation of optical Schrödinger cat states

Hendrik Hegels, Thomas Stolz, Gerhard Rempe, and Stephan Dürr

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Phys. Rev. A 113, 013708 – Published 2 January, 2026

DOI: https://doi.org/10.1103/nwry-xjsb

Abstract

We propose to use cavity Rydberg electromagnetically induced transparency to generate Schrödinger cat states of optical photons. We predict that this should make it possible to generate states with relatively large mean photon numbers. With existing technology, mean photon numbers around 30 seem feasible. The main limitation is photon loss during the process, which generates the state. The ability to tune the strength of the photon loss caused by atomic spontaneous emission makes it possible to have little decoherence despite significant photon loss during the generation of the state.

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Phys. Rev. A 113, 013708– Published 2 January, 2026
  • Received 2 September 2025
  • Accepted 8 December 2025
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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. Open access publication funded by Max Planck Society.

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