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arXiv · 2601.22506

Observation of Janus Chirality for Coherent Thermal Emission from Metasurfaces

Kaili Sun·Yangjian Cai·Maxim V. Gorkunov·Yuri Kivshar·Zhanghua Han
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Abstract

Metasurfaces emerged as a powerful tool for controlling thermal radiation, yet achieving coherent emission with opposite circular handednesses remains a highly challenging problem. Here, we demonstrate experimentally the Janus chiral thermal emission from metasurfaces with opposite circular handednesses on either side of a single device. We employ anisotropic metasurfaces supporting high-Q resonances with photonic flatbands enabling near-unity circular dichroism through in-plane symmetry control. Our experiments confirm the Janus coherent emission, and they are validated by the results of the coupled-mode theory. The flatband resonant metasurfaces enabling a control of chiral thermal emission provide an efficient platform for spin-controlled light-matter interaction.

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Kaili Sun, Yangjian Cai, Maxim V. Gorkunov, Yuri Kivshar, Zhanghua Han. 2026-01-30. Observation of Janus Chirality for Coherent Thermal Emission from Metasurfaces. https://arxiv.org/abs/2601.22506

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