Vortex Laser at Exceptional Point
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.
Cite
@article{arxiv.1607.08859,
title = {Vortex Laser at Exceptional Point},
author = {Xing-Yuan Wang and Hua-Zhou Chen and Ying Li and Bo Li and Ren-Min Ma},
journal= {arXiv preprint arXiv:1607.08859},
year = {2016}
}