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arXiv · 1905.08822

Spin-momentum locked modes on anti-phase boundaries in photonic crystals

Xianghong Kong·Yun Zhou·Gaobiao Xiao·Daniel F. Sievenpiper
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Abstract

An anti-phase boundary is formed by shifting a portion of photonic crystal lattice along the direction of periodicity. A spinning magnetic dipole is applied to excite edge modes on the anti-phase boundary. We show the unidirectional propagation of the edge modes which is also known as spin-momentum locking. Band inversion of the edge modes is discovered when we sweep the geometrical parameters, which leads to a change in the propagation direction. Also, an optimized source is applied to excite the unidirectional edge mode with high directivity.

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Xianghong Kong, Yun Zhou, Gaobiao Xiao, Daniel F. Sievenpiper. 2019-05-21. Spin-momentum locked modes on anti-phase boundaries in photonic crystals. https://doi.org/10.1364/oe.379672

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