Observation of quasi-two-dimensional Dirac fermions in ZrTe5

Abstract

Since the discovery of graphene, layered materials have attracted extensive interests owing to their unique electronic and optical characteristics. Among them, Dirac semimetal, one of the most appealing categories, has been a long-sought objective in layered systems beyond graphene. Recently, layered pentatelluride ZrTe5 was found to host signatures of Dirac semimetal. However, the low Fermi level in ZrTe5 strongly hinders a comprehensive understanding of the whole picture of electronic states through photoemission measurements, especially in the conduction band. Here, we report the observation of Dirac fermions in ZrTe5 through magneto-optics and magneto-transport. By applying magnetic field, we observe a square-root-B dependence of inter-Landau-level resonance and Shubnikov-de Haas (SdH) oscillations with non-trivial Berry phase, both of which are hallmarks of Dirac fermions. The angular-dependent SdH oscillations show a clear quasi-two-dimensional feature with highly anisotropic Fermi surface and band topology, in stark contrast to the 3D Dirac semimetal such as Cd3As2. This is further confirmed by the angle-dependent Berry phase measurements and the observation of bulk quantum Hall plateaus. The unique band dispersion is theoretically understood: the system is at the critical point between a 3D Dirac semimetal and a topological insulator phase. With the confined interlayer dispersion and reducible dimensionality, our work establishes ZrTe5 as an ideal platform for exploring exotic physical phenomena of Dirac fermions.

References in corpus (21)

• The electronic properties of graphene
• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Quantum interference and Klein tunneling in graphene heterojunctions
• Observation of the chiral magnetic effect in ZrTe5
• Observation of tunable bandgap and anisotropic Dirac semimetal state in black phosphorus
• Classification of stable three-dimensional Dirac semimetals with nontrivial topology
• Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit
• Topological origin of subgap conductance in insulating bilayer graphene
• Infrared spectroscopy of Landau levels in graphene
• Quantum transport evidence for a three-dimensional Dirac semimetal phase in Cd3As2
• Electronic Evidence of Temperature-Induced Lifshitz Transition and Topological Nature in ZrTe5
• Colloquium: Graphene spectroscopy
• Optical spectroscopy study of three dimensional Dirac semimetal ZrTe${}_5$
• Many-body interactions in quasi-freestanding graphene
• Quantum Hall effect in a bulk antiferromagnet EuMnBi${}_2$ with magnetically confined two-dimensional Dirac fermions
• Magneto-infrared spectroscopy of Landau levels and Zeeman splitting of three-dimensional massless Dirac Fermions in ZrTe${}_5$
• Velocity Renormalization and Carrier Lifetime in Graphene from Electron-Phonon Interaction
• Robust topological edge states at the perfect surface step edge of topological insulator ZrTe${}_5$
• Axial anomaly and longitudinal magnetoresistance of a generic three dimensional metal
• Coexistence of topological Dirac fermions in the surface and three-dimensional Dirac cone state in the bulk of ZrTe${}_5$ single crystal
• Persistence to high temperatures of interlayer coherence in an organic superconductor

Cited by in corpus (43)

• Weyl and Dirac Semimetals in Three Dimensional Solids
• Electronic Evidence of Temperature-Induced Lifshitz Transition and Topological Nature in ZrTe5
• Detection of sub-MeV Dark Matter with Three-Dimensional Dirac Materials
• High-pressure synthesis of Dirac materials: layered van der Waals bonded BeN${}_4$ polymorph
• Temperature-driven Topological Phase Transition and Intermediate Dirac Semimetal Phase in ZrTe${}_5$
• Giant Planar Hall Effect in the Dirac Semimetal ZrTe5
• Spectroscopic evidence for bulk-band inversion and three-dimensional massive Dirac fermions in ZrTe5
• Bipolar Conduction is the Origin of the Electronic Transition in Pentatellurides: Metallic vs. Semiconducting Behavior
• Anomalous thermoelectric effects of ZrTe${}_5$ in and beyond the quantum limit
• Chiral Landau levels in Weyl semimetal NbAs with multiple topological carriers
• Field induced topological phase transition from a three-dimensional Weyl semimetal to a two-dimensional massive Dirac metal in ZrTe5
• Direct observation of Landau level resonance and mass generation in Dirac semimetal Cd3As2 thin films
• Unraveling the Topological Phase of ZrTe${}_5$ via Magneto-infrared Spectroscopy
• Disruption of the accidental Dirac semimetal state in ZrTe${}_5$ under hydrostatic pressure
• Coexistence of topological Dirac fermions in the surface and three-dimensional Dirac cone state in the bulk of ZrTe${}_5$ single crystal
• Large Nernst effect and field enhanced transversal ZT in ZrTe5
• Landau level spectroscopy of massive Dirac fermions in single-crystalline ZrTe5 thin flakes
• Electrical transport in nano-thick ZrTe${}_5$ sheets: from three to two dimensions
• Unraveling the topology of ZrTe${}_5$ by changing temperature
• Electron Transport in Dirac and Weyl Semimetals
• Thermodynamic signatures for the existence of Dirac electrons in ZrTe5
• Dirac electron behavior and NMR evidence for topological band inversion in ZrTe5
• Semi-Dirac Fermions in a Topological Metal
• Dark Matter Direct Detection in Materials with Spin-Orbit Coupling
• Significant change in the electronic behavior associated with structural distortions in the single crystalline SrAg4As2
• From Dirac semimetals to topological phases in three dimensions: a coupled wire construction
• Distinguishing the gapped and Weyl semimetal scenario in ZrTe${}_5$: insights from an effective two-band model
• Veselago focusing of anisotropic massless Dirac fermions
• Magnetic-field-induced nonlinear transport in HfTe5
• Optical conductivity and resistivity in a four-band model for ZrTe${}_5$ from ab-initio calculations
• Signature of pressure-induced topological phase transition in ZrTe${}_5$
• Revealing the band structure of ZrTe${}_5$ using Multicarrier Transport
• Magnetotransport and Berry phase Tuning in Gd-doped Bi2Se3 Topological Insulator Single Crystals
• Correlated interaction effects in three-dimensional semi-Dirac semimetal
• Global phase diagram of Coulomb-interacting anisotropic Weyl semimetals with disorder
• Quasi-Dirac points in electron-energy spectra of crystals
• Isotropic Dirac fermion and anomalous oscillator strength of zeroth Landau level transition
• Semi-Dirac spin liquids and frustrated quantum magnetism on the trellis lattice
• Holographic entanglement renormalisation for fermionic quantum matter
• Effect of pressure on the transport properties and thermoelectric performance of Dirac semimetal ZrTe5
• Material realization of spinless, covalent-type Dirac semimetals in three dimensions
• Optical manipulation of the topological phase in ZrTe5 revealed by time- and angle-resolved photoemission
• First-principles studies of fermiology in topological phases of bulk ZrTe${}_5$