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arXiv · 1008.5156

PT-symmetry breaking and laser-absorber modes in optical scattering systems

Y. D. Chong·Li Ge·A. Douglas Stone
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Abstract

Using a scattering matrix formalism, we derive the general scattering properties of optical structures that are symmetric under a combination of parity and time-reversal (PT). We demonstrate the existence of a transition beween PT-symmetric scattering eigenstates, which are norm-preserving, and symmetry-broken pairs of eigenstates exhibiting net amplification and loss. The system proposed by Longhi, which can act simultaneously as a laser and coherent perfect absorber, occurs at discrete points in the broken symmetry phase, when a pole and zero of the S-matrix coincide.

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Y. D. Chong, Li Ge, A. Douglas Stone. 2011-01-27. PT-symmetry breaking and laser-absorber modes in optical scattering systems. https://doi.org/10.1103/physrevlett.106.093902

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