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arXiv · 1607.08859

Vortex Laser at Exceptional Point

Xing-Yuan Wang·Hua-Zhou Chen·Ying Li·Bo Li·Ren-Min Ma
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Abstract

The optical vortices carrying orbital angular momentum (OAM) are commonly generated by modulating the available conventional light beam. This article shows that a micro-laser operates at the exceptional point (EP) of the non-Hermitian quantum system can directly emit vortex laser with well-defined OAM at will. Two gratings (the refractive index modulation and along azimuthal direction and the grating protruding from the micro-ring cavity) modulate the eigenmode of a micro-ring cavity to be a vortex laser mode. The phase-matching condition ensures that we can tune the OAM of the vortex beam to be arbitrary orders by changing the grating protruding from the micro-ring cavity while the system is kept at EP. The results are obtained by analytical analysis and confirmed by 3D full wave simulations.

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Xing-Yuan Wang, Hua-Zhou Chen, Ying Li, Bo Li, Ren-Min Ma. 2016-07-29. Vortex Laser at Exceptional Point. https://arxiv.org/abs/1607.08859

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