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arXiv · 2203.06452

Lasing versus lasing without inversion in an optically thin gain medium near a metal surface

V. G. Bordo
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Abstract

A theory of lasing in an optically thin layer of active centers disposed at a metal surface is developed from first principles. The approach is based on a rigorous account of the local field in a close vicinity of a reflective surface which provides a feedback for dipole oscillations in active centers. It is demonstrated that the gain medium thickness plays a crucial role in the lasing condition and controls a switching from conventional lasing to lasing without inversion. The numerical calculations are carried out for erbium doped glass bordering a gold surface where radiation at telecom wavelength (1532 nm) can be generated.

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V. G. Bordo. 2022-03-12. Lasing versus lasing without inversion in an optically thin gain medium near a metal surface. https://doi.org/10.1364/josab.462562

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