Landau level spectroscopy of Bi${}_2$Te${}_3$

Abstract

Here we report on Landau level spectroscopy in magnetic fields up to 34 T performed on a thin film of topological insulator Bi${}_2$Te${}_3$ epitaxially grown on a BaF${}_2$ substrate. The observed response is consistent with the picture of a direct-gap semiconductor in which charge carriers closely resemble massive Dirac particles. The fundamental band gap reaches $E_g=(175\pm 5)$~meV at low temperatures and it is not located on the trigonal axis, thus displaying either six or twelvefold valley degeneracy. Notably, our magneto-optical data do not indicate any band inversion. This suggests that the fundamental band gap is relatively distant from the $\Gamma$ point where profound inversion exists andgives rise to relativistic-like surface states of Bi${}_2$Te${}_3$.

arXiv comment12 pages, 11 figures, to be published in Phys. Rev. B

References in corpus (25)

• Topological Insulators
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• First observation of Spin-Momentum Helical Locking in Bi2Se3 and Bi2Te3, demonstration of Topological-Order at 300K and a realization of topological-transport-regime
• Model Hamiltonian for Topological Insulators
• STM imaging of electronic waves on the surface of Bi${}_2$Te${}_3$: topologically protected surface states and hexagonal warping effects
• Persistence of Topological Order and Formation of Quantum Well States in Topological Insulators Bi2(Se,Te)3 under Ambient Conditions
• Quasiparticle Effects in the Bulk and Surface-State Bands of Bi2Se3 and Bi2Te3 Topological Insulators
• Quasi-classical cyclotron resonance of Dirac fermions in highly doped graphene
• Magneto-optics of massive Dirac fermions in bulk Bi2Se3
• Bulk Band Structure of Bi${}_2$Te${}_3$
• Fine structure of "zero-mode" Landau levels in HgTe/HgCdTe quantum wells
• Negative longitudinal magnetoresistance from anomalous N=0 Landau level in topological materials
• The quasiparticle band gap in the topological insulator Bi2Te3
• Anisotropic effect of warping on the lifetime broadening of topological surface states in angle-resolved photoemission from Bi${}_2$Te${}_3$
• Measure of Diracness in two-dimensional semiconductors
• Semirelativity in Semiconductors: a Review
• Cyclotron motion in the vicinity of a Lifshitz transition in graphite
• Interband absorption edge in topological insulators Bi${}_2$(Te${}_{1-x}$Se${}_x$)${}_3$
• Landau level spectroscopy of relativistic fermions with low Fermi velocity in Bi2Te3 three-dimensional topological insulator
• Infrared electrodynamics and ferromagnetism in the topological semiconductors Bi${}_2$Te${}_3$ and Mn-doped Bi${}_2$Te${}_3$
• Doping of Bi2Te3 using electron irradiation
• Avoided level crossing at the magnetic field induced topological phase transition due to spin-orbital mixing
• Theory of electron spin resonance in bulk topological insulators Bi2Se3, Bi2Te3 and Sb2Te3
• Nonperturbative Matrix Mechanics Approach to Spin-Split Landau Levels and g-Factor in Spin-Orbit Coupled Solids

Cited by in corpus (3)

• Semi-Dirac Fermions in a Topological Metal
• Electronic band structure of Sb2Te3
• Anisotropy in the dielectric function of Bi${}_2$Te${}_3$ from first principles: From the UV-visible to the infrared range