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arXiv · 2405.15715

Hyperbolic Shear Metasurfaces

Enrico Maria Renzi·Emanuele Galiffi·Xiang Ni·Andrea Alù
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Abstract

Polar dielectrics with low crystal symmetry and sharp phonon resonances can support hyperbolic shear polaritons - highly confined surface modes with frequency-dependent optical axes and asymmetric dissipation features. So far, these modes have been observed only in bulk natural materials at mid-infrared frequencies, with properties limited by available crystal geometries and phonon resonance strength. Here we introduce hyperbolic shear metasurfaces: ultrathin engineered surfaces supporting hyperbolic surface modes with symmetry-tailored axial dispersion and loss redistribution that can maximally enhance light-matter interactions. By engineering effective shear phenomena in these engineered surfaces, we demonstrate geometry-controlled, ultra-confined, low-loss hyperbolic surface waves with broadband Purcell enhancements, applicable across a broad range of the electromagnetic spectrum.

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Enrico Maria Renzi, Emanuele Galiffi, Xiang Ni, Andrea Alù. 2024-05-24. Hyperbolic Shear Metasurfaces. https://doi.org/10.1103/physrevlett.132.263803

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