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arXiv · 2109.10314

Chiral Surface Wave propagation with Anomalous Spin-momentum Locking

Sara M. Kandil·Dia'aaldin J. Bisharat·Daniel F. Sievenpiper
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Abstract

The ability to control the directionality of surface waves by manipulating its polarization has been of great significance for applications in spintronics and polarization-based optics. Surface waves with evanescent tails are found to possess an inherent in-plane transverse spin which is dependent on the propagation direction while an out-of-plane transverse spin does not naturally occur for surface waves and requires a specific surface design. Here, we introduce a new type of surface waves called chiral surface wave which has two transverse spins, an in-plane one that is inherent to any surface wave and an out-of-plane spin which is enforced by the design due to strong x-to-y coupling and broken rotational symmetry. The two transverse spins are locked to the momentum. Our study opens a new direction for metasurface designs with enhanced and controlled spin-orbit interaction by adding an extra degree of freedom to control the propagation direction as well as the transverse spin of surface waves.

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Sara M. Kandil, Dia'aaldin J. Bisharat, Daniel F. Sievenpiper. 2021-09-21. Chiral Surface Wave propagation with Anomalous Spin-momentum Locking. https://arxiv.org/abs/2109.10314

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