Metamaterials enable unprecedented control over linear and nonlinear light manipulation, offering novel capabilities for optical wave propagation, amplitude, phase, and wavefront modulation and enhanced light-matter interactions, with significant implications for applications in imaging, telecommunications, and quantum technologies. In the first part of this talk, 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 and advanced imaging techniques. In the second part of this talk, we will discuss the design and experimental demonstration of the nonlinear, periodically stacked, all-dielectric metasurfaces, enabling an efficient nonlinear wavelength conversion facilitated by the synergy of metamaterial and photonic crystal platforms.
Litchinitser et al. (Tue,) studied this question.