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arXiv · 2003.07352

A Nanoscale Coherent Light Source

Raphael Holzinger·David Plankensteiner·Laurin Ostermann·Helmut Ritsch
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Abstract

Generically, a laser is composed of an optical resonator coupled to a gain medium. If the light amplification via stimulated emission dominates the mirror losses, the emitted light is coherent. Recent studies have shown that sub-wavelength sized rings of quantum emitters possess subradiant eigenmodes which mimic high-Q optical resonators. We add a continuously pumped atom as a gain medium in the ring's center creating a minimalistic coherent light source. The system behaves like a thresholdless laser, featuring a narrow linewidth well below the natural linewidth of the constituent atoms.

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Raphael Holzinger, David Plankensteiner, Laurin Ostermann, Helmut Ritsch. 2020-03-16. A Nanoscale Coherent Light Source. https://doi.org/10.1103/physrevlett.124.253603

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