Ultrahigh magnetic field spectroscopy reveals the band structure of the 3D topological insulator Bi${}_2$Se${}_3$

Abstract

We have investigated the band structure at the $\Gamma$ point of the three-dimensional (3D) topological insulator Bi${}_2$Se${}_3$ using magneto-spectroscopy over a wide range of energies ($0.55-2.2$\,eV) and in ultrahigh magnetic fields up to 150\,T. At such high energies ($E>0.6$\,eV) the parabolic approximation for the massive Dirac fermions breaks down and the Landau level dispersion becomes nonlinear. At even higher energies around 0.99 and 1.6 eV, new additional strong absorptions are observed with a temperature and magnetic-field dependence which suggest that they originate from higher band gaps. Spin orbit splittings for the further lying conduction and valence bands are found to be 0.196 and 0.264 eV.

References in corpus (4)

• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Bulk Fermi surface coexistence with Dirac surface state in Bi${}_2$Se${}_3$: a comparison of photoemission and Shubnikov-de Haas measurements
• Magneto-optics of massive Dirac fermions in bulk Bi2Se3
• Relativistic k.p Hamiltonians for centrosymmetric topological insulators from ab initio wave functions

Cited by in corpus (4)

• Electron-Hole Asymmetry of Surface States in Topological Insulator Sb2Te3 Thin Films Revealed by Magneto-Infrared Spectroscopy
• Addressing Shape and Extent of Weyl cones in TaAs by Landau level spectroscopy
• Isotropic Dirac fermion and anomalous oscillator strength of zeroth Landau level transition
• Landau level spectroscopy in current solid state physics