Decoherence in a PT -Symmetric Qubit

Authors

  • J.M. Bhat National Institute of Technology Rourkela
  • M.Q. Lone Department of Physics, University of Kashmir
  • S. Datta National Institute of Technology Rourkela
  • G.N. Dar Department of Physics, University of Kashmir
  • A. Farouk Faculty of Computer and Information Sciences, Mansoura University

DOI:

https://doi.org/10.15407/ujpe68.2.101

Keywords:

PT-symmetry, decoherence, system-bath correlations

Abstract

We investigate the decoherence in a PT -symmetric qubit coupled with a bosonic bath. Using canonical transformations, we map the non-Hermitian Hamiltonian representing the PT-symmetric qubit to a spin boson model. Identifying the parameter α that demarcates the hermiticity and non-hermiticity in the model, we show that the qubit does not decohere at the transition from the real eigen spectrum to a complex eigen spectrum. Using a general class of spectral densities, the strong suppression of the decoherence is observed due to both vacuum and thermal fluctuations of the bath, and the initial correlations hold, as we approach the transition point.

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Published

2023-04-20

How to Cite

Bhat, J., Lone, M., Datta, S., Dar, G., & Farouk, A. (2023). Decoherence in a PT -Symmetric Qubit. Ukrainian Journal of Physics, 68(2), 101. https://doi.org/10.15407/ujpe68.2.101

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Section

Optics, atoms and molecules