Observation of PT-symmetry breaking in complex optical potentials.

  title={Observation of PT-symmetry breaking in complex optical potentials.},
  author={A. Guo and Gregory J. Salamo and David Duchesne and Roberto Morandotti and Maite Volatier-Ravat and Vincent Aimez and Georgios A. Siviloglou and Demetrios N. Christodoulides},
  journal={Physical review letters},
  volume={103 9},
In 1998, Bender and Boettcher found that a wide class of Hamiltonians, even though non-Hermitian, can still exhibit entirely real spectra provided that they obey parity-time requirements or PT symmetry. Here we demonstrate experimentally passive PT-symmetry breaking within the realm of optics. This phase transition leads to a loss induced optical transparency in specially designed pseudo-Hermitian guiding potentials. 

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