Quantum entropy of systems described by non-Hermitian Hamiltonians

@article{Sergi2015QuantumEO,
  title={Quantum entropy of systems described by non-Hermitian Hamiltonians},
  author={Alessandro Sergi and Konstantin G. Zloshchastiev},
  journal={Journal of Statistical Mechanics: Theory and Experiment},
  year={2015},
  volume={2016}
}
We study the quantum entropy of systems that are described by general non-Hermitian Hamiltonians, including those which can model the effects of sinks or sources. We generalize the von Neumann entropy to the non-Hermitian case and find that one needs both the normalized and non-normalized density operators in order to properly describe irreversible processes. It turns out that such a generalization monitors the onset of disorder in quantum dissipative systems. We give arguments for why one can… 
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