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arXiv · 1107.1873

Spectral Singularities of a Complex Spherical Barrier Potential and Their Optical Realization

Ali Mostafazadeh·Mustafa Sarisaman
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Abstract

The mathematical notion of a spectral singularity admits a physical interpretation as a zero-width resonance. It finds an optical realization as a certain type of lasing effect that occurs at the threshold gain. We explore spectral singularities of a complex spherical barrier potential and study their realization as transverse spherical electromagnetic waves emitted by a gain medium with a spherical geometry. In particular, for a typical dye laser material, we obtain a lower bound on the size of the gain medium for the occurence of this kind of spectral singularities.

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Ali Mostafazadeh, Mustafa Sarisaman. 2011-07-10. Spectral Singularities of a Complex Spherical Barrier Potential and Their Optical Realization. https://doi.org/10.1016/j.physleta.2011.07.052

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