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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.
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Ellipticity‐Controlled Exceptional Points and Cross‐Polarized Phase Singularities in Multi‐Layer Silicon Guided Mode Resonant Metasurfaces
Abstract Precise control over light polarization is critical for advancing technologies in telecommunications, quantum computing, and image sensing. However, existing methods for manipulating polarization around exceptional points (EPs) in non‐Hermitian systems have exclusively focused on circular polarization and work with reflected light. To address this limitation, a novel metasurface platform with high‐Q resonators is developed that enables tunable control of polarization exceptional points across arbitrary ellipticity for transmitted light. This design employs orthogonally polarized guided mode resonators in a two‐layer silicon metasurface, where careful tuning of the dipolar guided mode resonances (DGMRs) and layer spacing allows us to control the ellipticity of EPs. By leveraging high‐quality factor resonances, strong orthogonal mode coupling over distances up to a quarter wavelength is achieved. This platform exhibits omnipolarizer behavior and the corresponding phase singularity can imprint phase shifts from 0 to 2π with small perturbations in the geometry. This approach opens new possibilities for polarization control and programmable wavefront shaping, offering significant potential for next‐generation optical devices.
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- PAR ID:
- 10636439
- Publisher / Repository:
- Wiley-VCH
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 13
- Issue:
- 26
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/adom.202500731
