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arXiv · 2406.05016

Nano-Focusing of Vortex Beams with Hyperbolic Metamaterials

Wenhao Li·Jacob LaMountain·Evan Simmons·Anthony Clabeau·Robel Y. Bekele·Jason D. Myers·Takashige Omatsu·Jesse Frantz·Viktor A. Podolskiy·Natalia M. Litchinitser
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Abstract

The synergy of judiciously engineered nanostructures and complex topology of light creates unprecedented opportunities for tailoring light-matter interactions on the nanoscale. Electromagnetic waves can carry multiple units of angular momentum per photon, stemming from both spin and orbital angular momentum contributions, offering a potential route for modifying the optical transition selection rules. However, the size difference between a vortex beam and quantum objects limits the interaction strength and the angular momentum exchange. Here, we demonstrate the sub-diffraction-limited focusing of a vortex beam using the high in-plane wave number modes present in hyperbolic metamaterials. The spin-orbit interaction within the hyperbolic structure gives rise to the formation of an optical skyrmion with a deep subwavelength structure, which may enable the exploration of new light-matter interaction phenomena.

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Wenhao Li, Jacob LaMountain, Evan Simmons, Anthony Clabeau, Robel Y. Bekele, Jason D. Myers, Takashige Omatsu, Jesse Frantz, Viktor A. Podolskiy, Natalia M. Litchinitser. 2024-06-07. Nano-Focusing of Vortex Beams with Hyperbolic Metamaterials. https://arxiv.org/abs/2406.05016

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