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ABSTRACT When arranged in a metasurface, the collective enhancement of field interactions within scattering elements enables precise control over the incident light phase and amplitude. In this work, we analyze collective multipolar resonances in metasurfaces that arise from the spatially extended nature of electromagnetic interactions within these structures, with particular emphasis on MXene metasurfaces. This collective scattering leads to unique and tunable resonance behaviors that reach beyond the simple dipolar approximations, thus enabling advanced manipulation of light at subwavelength scales. We also explore resonances in the scatterers and metasurfaces made of different materials, categorizing them into lossy materials, including transition metal dichalcogenides and conventional metals, and high‐refractive‐index materials, such as silicon. We observe the excitation of MXene multipolar resonances across the visible‐ and infrared‐wavelength spectra and demonstrate their control through the design of scattering elements of the metasurface. We show that periodic lattice arrays support strong localized resonances through the collective response of individual nanoresonators and that one can control multipolar resonances by engineering metasurface nanoresonators and their distribution. 

Abstract Electron‐beam deposition stands as a versatile technique utilized for the accurate and controlled thin‐film deposition of a wide range of materials that readily undergo evaporation. However, silicon, a commonly used material, is prone to oxidation during the deposition process because of the presence of water vapors and oxygen in the chamber. To overcome this challenge, a tailored approach is developed that involves controlling the deposition conditions, including the base pressure in the chamber and the deposition rate. Silicon oxidation is successfully overcome, and this results in achieving refractive index values comparable to those obtained with alternative deposition methods for amorphous silicon. The research shows that the deposition conditions can be utilized effectively to tune the refractive index, providing flexibility in achieving the desired optical properties. It is demonstrated that Mie‐resonant metasurfaces exhibit strong collective resonances, driven by the coherent coupling of Mie modes within the periodic nanoantenna lattice, as evidenced by distinct spectral features in the scattering response. These resonances are observed to be highly tunable, with spectral shifts corresponding to controlled variations in the electron‐beam deposition parameters and silicon oxidation. The approach enables silicon deposition for metasurfaces, which presents exciting possibilities for tailoring and designing advanced nanostructures with unique optical characteristics. 

Applying coatings that suppress the radiance changes related to temperature-dependent blackbody emission enables temperature-independent optical and sensing systems. Phase-change materials can significantly modify their optical properties within their transition window, but compensating for the large mid-wave infrared (MWIR, 3–5 µm) variation is demanding: blackbody radiance at 3 µm increases nearly 10-fold as the temperature rises from 30 °C to 80 °C. Vanadium dioxide VO2, whose insulator–metal transition offers a sharp contrast and a low-loss insulating state, is attractive for applications in thermal management, but simple thin-film designs cannot provide full compensation. We demonstrate metasurface coatings that provide this compensation by constructing an array of metal–VO2–metal antennas tuned to maintain constant thermal emission at a target wavelength over a temperature range of 30 °C to 80 °C. Antennas of several lateral sizes are combined, so their individual resonances collectively track the Planck change. This design provides both optical contrast and the correct temperature derivative, which are unattainable with homogeneous layers. Our approach results in a negligible apparent temperature change of the metasurface across the 30–80 °C range, effectively masking thermal signatures from MWIR detectors stemming from the low losses of VO2. 

The electro‐optic (EO) effect is one of the physical mechanisms enabling the dynamic response of metasurfaces, which motivates the analysis of nanoantenna arrays integrated with EO materials. It was shown earlier that chalcophosphate Sn₂P₂S₆metasurfaces can enable significant shifts of multipolar resonances by enhancing the EO response near the Curie temperature. The present work explores how the refractive index of EO materials impacts resonance shifts in metasurfaces with multipolar resonances. It is numerically demonstrated that EO nanoantennas can support pronounced multipolar resonances despite their moderate refractive index, enabling strong light confinement and substantial EO tuning, and that multipolar components of even parity exhibit the highest sensitivity to variations in the refractive index of the nanoantennas. For moderate refractive indices varying from 2.3 to 3.0, it is found that, for a given resonance, the wavelength shift resulting from a refractive index change has a relatively weak dependence on the index itself. This suggests that the refractive index plays only a marginal role in enhancing the EO shift in active photonic devices, and instead, other considerations for material selection, such as the EO coefficient magnitude, the transparency window, and ease of processing, should be of primary concern. 

High-refractive-index nanoantennas have attracted significant attention lately because of the strong excitations of electric and magnetic resonances in these nanoantennas. Here, we theoretically investigate the excitation of multipolar Mie resonances in high-refractive-index nanoantennas that are immersed in a negative-index medium. Our analysis shows a significant enhancement of magnetic resonances in this case. Furthermore, the magnetic dipolar and quadrupolar resonances exhibit a π-shift compared to these magnetic resonances in a conventional medium, which stems from the “left-handedness” of the negative-index medium. As a result, the spectral regions where electric and magnetic resonances are in-phase or out-of-phase complement, or opposite, to those in a conventional medium. Most importantly, we demonstrate nanoantenna magnetic resonances in two practical cases of negative-index media realized with common materials, such as multilayer structures with surface waves with negative effective mode index and fishnet metamaterial. These findings represent significant progress toward the realization of hybrid emitting structures that exhibit transitions with both electric and magnetic dipolar characteristics and pave the way for greater flexibility in controlling radiation patterns from quantum emitters. 

Metasurfaces, composed of engineered nanoantennas, enable unprecedented control over electromagnetic waves by leveraging multipolar resonances to tailor light–matter interactions. This review explores key physical mechanisms that govern their optical properties, including the role of multipolar resonances in shaping metasurface responses, the emergence of bound states in the continuum (BICs) that support high-quality factor modes, and the Purcell effect, which enhances spontaneous emission rates at the nanoscale. These effects collectively underpin the design of advanced photonic devices with tailored spectral, angular, and polarization-dependent properties. This review discusses recent advances in metasurfaces and applications based on them, highlighting research that employs full-wave numerical simulations, analytical and semi-analytic techniques, multipolar decomposition, nanofabrication, and experimental characterization to explore the interplay of multipolar resonances, bound and quasi-bound states, and enhanced light–matter interactions. A particular focus is given to metasurface-enhanced photodetectors, where structured nanoantennas improve light absorption, spectral selectivity, and quantum efficiency. By integrating metasurfaces with conventional photodetector architectures, it is possible to enhance responsivity, engineer photocarrier generation rates, and even enable functionalities such as polarization-sensitive detection. The interplay between multipolar resonances, BICs, and emission control mechanisms provides a unified framework for designing next-generation optoelectronic devices. This review consolidates recent progress in these areas, emphasizing the potential of metasurface-based approaches for high-performance sensing, imaging, and energy-harvesting applications.