Breaking of PT-symmetry in bounded and unbounded scattering systems

  title={Breaking of PT-symmetry in bounded and unbounded scattering systems},
  author={Philipp Ambichl and Konstantinos G. Makris and Li Ge and Yidong Chong and A. Douglas Stone and Stefan Rotter},
  journal={arXiv: Optics},
PT-symmetric scattering systems with balanced gain and loss can undergo a symmetry-breaking transition in which the eigenvalues of the non-unitary scattering matrix change their phase shifts from real to complex values. We relate the PT-symmetry breaking points of such an unbounded scattering system to those of underlying bounded systems. In particular, we show how the PT-thresholds in the scattering matrix of the unbounded system translate into analogous transitions in the Robin boundary… 
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