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arXiv · 2412.16949

Optical Signature of Flat Bands in Topological Hourglass Semimetal Nb3SiTe6

Shize Cao·Cuiwei Zhang·Yueshan Xu·Jianzhou Zhao·Youguo Shi·Yun-Ze Long·Jianlin Luo·Zhi-Guo Chen
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Abstract

Flat electronic bands in condensed matter provide a rich avenue for exploring novel quantum phenomena. Here, we report an optical spectroscopy study of a topological hourglass semimetal Nb3SiTe6 with the electric field of the incident light parallel to its crystalline ab-plane. The ab-plane optical conductivity spectra of Nb3SiTe6 single crystals exhibit a remarkable peak-like feature around 1.20 eV, which is mainly contributed by the direct optical transitions between the two ab-initio-calculation-derived flat bands along the momentum direction Z-U. Our results pave the way for investigating exotic quantum phenomena based on the flat bands in topological hourglass semimetals.

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Shize Cao, Cuiwei Zhang, Yueshan Xu, Jianzhou Zhao, Youguo Shi, Yun-Ze Long, Jianlin Luo, Zhi-Guo Chen. 2024-12-22. Optical Signature of Flat Bands in Topological Hourglass Semimetal Nb3SiTe6. https://doi.org/10.1088/1674-1056%2Fad9e9c

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