On the observability and asymmetry of adiabatic state flips generated by exceptional points

@article{Uzdin2011OnTO,
  title={On the observability and asymmetry of adiabatic state flips generated by exceptional points},
  author={Raam Uzdin and A. T. Mailybaev and Nimrod Moiseyev},
  journal={Journal of Physics A: Mathematical and Theoretical},
  year={2011},
  volume={44}
}
In open quantum systems where the effective Hamiltonian is not Hermitian, it is known that the adiabatic (or instantaneous) basis can be multivalued: by adiabatically transporting an eigenstate along a closed loop in the parameter space of the Hamiltonian, it is possible to end up in an eigenstate different from the initial eigenstate. This ‘adiabatic flip’ effect is an outcome of the appearance of a degeneracy known as an ‘exceptional point’ inside the loop. We show that contrary to what is… 

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