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arXiv · 2506.06872

Broadband Low-loss Unidirectional Reflection On-chip with Asymmetric Dielectric Metasurface

Heijun Jeong·Zeki Hayran·Yuan Liu·Yahui Xiao·Hwaseob Lee·Zi Wang·Jonathan Klamkin·Francesco Monticone·Tingyi Gu
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Abstract

Metasurface has emerged as a powerful platform for controlling light at subwavelength thickness, enabling new functionalities for imaging, polarization manipulation, and angular momentum conversion within a flat surface. We explored an integrated asymmetric metasurface simultaneously achieving broadband, low loss forward power transmission, and significant back reflection sup-pression in multi-mode waveguides. The tapering along the direction of light propagation leads to low loss and space-efficient mode conversion. Enhanced by a double-flipped structure, a thin (2.5 micrometer) metasurface can simultaneously achieve high conversion efficiency (>80 percent), and back-reflection efficiency of 90 percent over a 200 nm wavelength range. Such single sided reflectors can be one of the enabling components for gain-integrated adaptive optics on a chip.

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Heijun Jeong, Zeki Hayran, Yuan Liu, Yahui Xiao, Hwaseob Lee, Zi Wang, Jonathan Klamkin, Francesco Monticone, Tingyi Gu. 2025-06-07. Broadband Low-loss Unidirectional Reflection On-chip with Asymmetric Dielectric Metasurface. https://doi.org/10.1002/lpor.202500216

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