Optical signature of flat bands in topological hourglass semimetal Nb₃SiTe₆

【摘要】 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.更多还原

【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.更多还原