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arXiv · 2003.11402

Topological charge of finite-size photonic crystal modes

Zhixin Wang·Yong Liang·Mattias Beck·Giacomo Scalari·Jérôme Faist
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Abstract

Topological charges are the winding numbers of polarization vectors around the vortex centers of far-field radiation. In this work, the topological charge of photonic crystal modes is theoretically analyzed using an envelope function approach. A group of modes is discovered with unique polarization properties dictated by their non-trivial envelope functions. Experimentally, lasing operation on such mode is demonstrated in an electrically pumped mid-infrared photonic crystal surface-emitting laser with high slope efficiency. The topological charge is directly observed from the polarization properties of single-mode laser emission.

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Zhixin Wang, Yong Liang, Mattias Beck, Giacomo Scalari, Jérôme Faist. 2020-03-25. Topological charge of finite-size photonic crystal modes. https://doi.org/10.1103/physrevb.102.045122

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