Spectroscopic evidence for a type II Weyl semimetallic state in MoTe2.

  title={Spectroscopic evidence for a type II Weyl semimetallic state in MoTe2.},
  author={Lunan Huang and Timothy M. McCormick and Masayuki Ochi and Zhiying Zhao and Michi-to Suzuki and Ryotaro Arita and Yun Wu and Daixiang Mou and Huibo Cao and Jiaqiang Yan and Nandini Trivedi and Adam Kaminski},
  journal={Nature materials},
  volume={15 11},
In a type I Dirac or Weyl semimetal, the low-energy states are squeezed to a single point in momentum space when the chemical potential μ is tuned precisely to the Dirac/Weyl point. Recently, a type II Weyl semimetal was predicted to exist, where the Weyl states connect hole and electron bands, separated by an indirect gap. This leads to unusual energy states, where hole and electron pockets touch at the Weyl point. Here we present the discovery of a type II topological Weyl semimetal state in… 

Figures, Tables, and Topics from this paper

Evidence for topological type-II Weyl semimetal WTe2
Exotic transport properties of type-II Weyl semimetals have been predicted but are yet to be experimentally evidenced and evidences of an anisotropy of negative magnetoresistance and a quantum oscillation arising from the predicted Weyl orbit in the type- II WeylSemimetal WTe2 are reported.
Signature of type-II Weyl semimetal phase in MoTe2
This work directly visualize the electronic structure of MoTe2, a recently proposed type-II TWS, using angle-resolved photoemission spectroscopy (ARPES), and unravels the unique surface Fermi arcs, in good agreement with ab initio calculations that have nontrivial topological nature.
Searching for topological Fermi arcs via quasiparticle interference on a type-II Weyl semimetal MoTe2
Weyl semimetals display a novel topological phase of matter where the Weyl nodes emerge in pairs of opposite chirality and can be seen as either a source or a sink of Berry curvature. The exotic
Observation of Weyl Nodes in Robust Type-II Weyl Semimetal WP_{2}.
The results ascertain that, due to the spin-orbit coupling, the Weyl nodes originate from the splitting of fourfold degenerate band-crossing points with Chern numbers C=±2 induced by the crystal symmetries of WP_{2}, which is unique among all the discovered WSMs.
Quasiparticle interference on type-I and type-II Weyl semimetal surfaces: a review
Abstract Weyl semimetals are a new member of the topological materials family, featuring a pair of singly degenerate Weyl cones with linear dispersion around the nodes in the bulk, and Fermi arcs on
Discovery of a new type of topological Weyl fermion semimetal state in MoxW1−xTe2
It is found that certain Weyl points are at the Fermi level, making MoxW1−xTe2 a promising platform for transport and optics experiments on Weyl semimetals.
Electronic properties of candidate type-II Weyl semimetal WTe 2 . A review perspective
Currently, there is a flurry of research interest on materials with an unconventional electronic structure, and we have already seen significant progress in their understanding and engineering
Topological surface Fermi arcs in the magnetic Weyl semimetal Co3Sn2S2
Very recently, the half-metallic compound Co3Sn2S2 was proposed to be a magnetic Weyl semimetal (WSM) with Weyl points only 60 meV above the Fermi level E-F. Owing to the low charge carrier density
Visualizing Type-II Weyl Points in Tungsten Ditelluride by Quasiparticle Interference.
Experimental proof that WTe2 is a type-II WSM is presented, and energy-dependent quasiparticle interference patterns are measured with a cryogenic scanning tunneling microscope, revealing the position of the Weyl point and its connection with the Fermi arc surface states, in agreement with prior theoretical predictions.
Universal response of the type-II Weyl semimetals phase diagram
The discovery of Weyl semimetals represents a significant advance in topological band theory. They paradigmatically enlarged the classification of topological materials to gapless systems while


MoTe2: Weyl and Line Node Topological Metal
Topological metals exhibit unremovable degeneracies in the band structure close to the Fermi level. These degeneracies can come in many types, the most basic of which are point (Weyl) and line nodes,
Weyl semimetal phase in the non-centrosymmetric compound TaAs
Experiments show that TaAs is a three-dimensional topological Weyl semimetal. Three-dimensional (3D) topologicalWeyl semimetals (TWSs) represent a state of quantum matter with unusual electronic
Type-II Weyl semimetals
This work proposes the existence of a previously overlooked type of Weyl fermion that emerges at the boundary between electron and hole pockets in a new phase of matter and discovers a type-II Weyl point, which is still a protected crossing, but appears at the contact of electron and Hole pockets in type- II Weyl semimetals.
Observation of Weyl nodes in TaAs
Experiments show that TaAs is a three-dimensional topological Weyl semimetal. In 1929, H. Weyl proposed that the massless solution of the Dirac equation represents a pair of a new type of particles,
Discovery of a Weyl fermion semimetal and topological Fermi arcs
The experimental discovery of a Weyl semimetal, tantalum arsenide (TaAs), using photoemission spectroscopy, which finds that Fermi arcs terminate on the Weyl fermion nodes, consistent with their topological character.
Topological nodal semimetals
We present a study of “nodal-semimetal” phases in which nondegenerate conduction and valence bands touch at points (the “Weyl semimetal”) or lines (the “line-node semimetal”) in three-dimensional
Topological semimetal and Fermi-arc surface states in the electronic structure of pyrochlore iridates
We investigate novel phases that emerge from the interplay of electron correlations and strong spin-orbit interactions. We focus on describing the topological semimetal, a three-dimensional phase of
Discovery of a Weyl fermion state with Fermi arcs in niobium arsenide
Three types of fermions play a fundamental role in our understanding of nature: Dirac, Majorana and Weyl. Whereas Dirac fermions have been known for decades, the latter two have not been observed as
Experimental discovery of Weyl semimetal TaAs
Weyl semimetals are a class of materials that can be regarded as three-dimensional analogs of graphene breaking time reversal or inversion symmetry. Electrons in a Weyl semimetal behave as Weyl
Discovery of a Three-Dimensional Topological Dirac Semimetal, Na3Bi
Na3Bi is established as a model system for 3D TDSs, which can serve as an ideal platform for the systematic study of quantum phase transitions between rich topological quantum states, and the robustness of 3D Dirac fermions in Na3Bi against in situ surface doping is demonstrated.