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arXiv · 1406.2537

Spontaneous Parity-Time Symmetry Breaking in Moving Media

M. G. Silveirinha
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Abstract

Optical instabilities in moving media are linked to a spontaneous parity-time symmetry breaking of the system. It is shown that in general the time evolution of the electromagnetic waves in moving media is determined by a non-Hermitian parity-time symmetric operator. For lossless systems the frequency spectrum of the time evolution operator may be complex valued, and has a mirror symmetry with respect to the real-frequency axis. The possibility of optical amplification of a light pulse in the broken parity-time symmetry regime is demonstrated.

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M. G. Silveirinha. 2014-06-10. Spontaneous Parity-Time Symmetry Breaking in Moving Media. https://doi.org/10.1103/physreva.90.013842

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