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arXiv · 1911.09540

Dirac-vortex topological cavity

Xiaomei Gao·Lechen Yang·Hao Lin·Lang Zhang·Jiafang Li·Fang Bo·Zhong Wang·Ling Lu
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Abstract

Cavity design is crucial for single-mode semiconductor lasers such as the distributed feedback (DFB) and vertical-cavity surface-emitting lasers (VCSEL). By recognizing that both optical resonators feature a single mid-gap mode localized at the topological defect in a one-dimensional (1D) lattice, we generalize the topological cavity design into 2D using a honeycomb photonic crystal with a vortex Dirac mass -- the analog of Jackiw-Rossi zero modes. We theoretically predict and experimentally demonstrate that such a Dirac-vortex cavity can have a tunable mode area across a few orders of magnitudes, arbitrary mode degeneracy, robustly large free-spectral-range, vector-beam output of low divergence, and compatibility with high-index substrates. This topological cavity could enable photonic crystal surface-emitting lasers (PCSEL) with stabler single-mode operation.

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Xiaomei Gao, Lechen Yang, Hao Lin, Lang Zhang, Jiafang Li, Fang Bo, Zhong Wang, Ling Lu. 2019-11-21. Dirac-vortex topological cavity. https://doi.org/10.1038/s41565-020-0773-7

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