Magneto-infrared spectroscopy of Landau levels and Zeeman splitting of three-dimensional massless Dirac Fermions in ZrTe₅

2015/06/30 by R. Y. Chen, Z. G. Chen, X. -Y. Song +4 · 2 citations
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.mtrl-sci

paper · pdf · doi:10.1103/physrevlett.115.176404

published as Phys. Rev. Lett. 115, 176404 (2015) · Editors' Suggestion

arxiv created 2015/10/22 · arxiv updated 2015/10/28

Abstract

We present a magneto-infrared spectroscopy study on a newly identified three-dimensional (3D) Dirac semimetal ZrTe₅. We observe clear transitions between Landau levels and their further splitting under magnetic field. Both the sequence of transitions and their field dependence follow quantitatively the relation expected for 3D massless Dirac fermions. The measurement also reveals an exceptionally low magnetic field needed to drive the compound into its quantum limit, demonstrating that ZrTe₅ is an extremely clean system and ideal platform for studying 3D Dirac fermions. The splitting of the Landau levels provides a direct and bulk spectroscopic evidence that a relatively weak magnetic field can produce a sizeable Zeeman effect on the 3D Dirac fermions, which lifts the spin degeneracy of Landau levels. Our analysis indicates that the compound evolves from a Dirac semimetal into a topological line-node semimetal under current magnetic field configuration.

Cited by

• DFT based insights into elastic, thermophysical, electronic and optical properties of topological insulators XTe5 (X = Zr, Hf)
• Dynamics of surface electrons in a topological insulator: cyclotron resonance at room temperature