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arXiv · 1205.4560

Self-dual Spectral Singularities and Coherent Perfect Absorbing Lasers without PT-symmetry

Ali Mostafazadeh
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Abstract

A PT-symmetric optically active medium that lases at the threshold gain also acts as a complete perfect absorber at the laser wavelength. This is because spectral singularities of PT-symmetric complex potentials are always accompanied by their time-reversal dual. We investigate the significance of PT-symmetry for the appearance of these self-dual spectral singularities. In particular, using a realistic optical system we show that self-dual spectral singularities can emerge also for non-PT-symmetric configurations. This signifies the existence of non-PT-symmetric CPA-lasers.

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quant-phhep-thmath-phmath.MPphysics.optics

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Ali Mostafazadeh. 2012-05-21. Self-dual Spectral Singularities and Coherent Perfect Absorbing Lasers without PT-symmetry. https://doi.org/10.1088/1751-8113/45/44/444024

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