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arXiv · 2506.20871

All-Dielectric Metasurface with a Two-Dimensional Locally Flat Photonic Band

Minho Choi·Christopher Munley·Virat Tara·Arnab Manna·Johannes Fröch·Arthur Barnard·Arka Majumdar
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Abstract

Photonic flatbands offer promising light-matter interaction due to their unique slow-light nature. In recent years, flatbands have also attracted significant interest in optical engineering because of their angle-insensitive resonant characteristics. However, to date, no studies have reported the dispersionless behavior of flatbands under arbitrary two-dimensional incident angles. Here, we present a two-dimensional photonic flatband created using a silicon metasurface with a Lieb lattice-inspired structure which demonstrates a locally flat photonic band for both transverse electric (TE) and transverse magnetic (TM) polarized light. Employing Fourier imaging, we analyze the energy-momentum dispersion of the flatband metasurface under arbitrary two-dimensional incident angles, demonstrating dispersionless flatbands with a change in resonance within $\pm2 nm$ up to $\pm24\^o$ or $\pm5\^o$, depending on the polarization state and incident angle. This geometry can be adapted for various applications in local field enhancement, enhanced photodetection, and augmented reality displays.

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Minho Choi, Christopher Munley, Virat Tara, Arnab Manna, Johannes Fröch, Arthur Barnard, Arka Majumdar. 2025-06-25. All-Dielectric Metasurface with a Two-Dimensional Locally Flat Photonic Band. https://arxiv.org/abs/2506.20871

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