# Observation of PT-symmetry breaking in complex optical potentials.

@article{Guo2009ObservationOP, 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}, year={2009}, volume={103 9}, pages={ 093902 } }

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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