Metasurfaces

This area combines work on robust dielectric metasurfaces and meta-optical devices with research of electromagnetic basis of magnetic resonance imaging. The optical part is devoted to Huygens metasurfaces, whose focusing and beam deflection properties remain stable under realistic manufacturing and operational fluctuations. These include arrays of disk meta-atoms separated by low-index materials, metagratings, deflectors, and metalenses. We are separately developing methods for quantitative assessment of stability and tolerance, linking analysis of sensitivities to geometry, refractive index, and thickness of an interlayer, as well as roughness, incidence angle, and polarization, with experimental benchmarking of efficiency and aberrations. This is accomplished through inverse design and machine learning aimed at disorder tolerance, as well as broadband and achromatic strategies compatible with scalable manufacturing and metrology.

In magnetic resonance imaging, we shift attention to radiofrequency and gradient coils, shielding systems, and associated signal and image processing methods. We study high-density parallel transmit and receive coil arrays for accelerated imaging, solutions for ultra-high fields with significant electromagnetic wave propagation effects, innovations in gradient coil technology, and advanced electromagnetic modeling methods for assessing specific absorption rate and patient safety. New materials, including metamaterials and high-temperature superconductors, computational methods, and integrated system solutions expanding the capabilities of clinical MRI are separately investigated.