*typical representative size, areas/dimensions may vary
**item with a lead time of 2-3 weeks, please contact for more information
|| ~0.7 eV 
||Tungsten telluride, Tungsten (IV) telluride
Transition metal dichalcogenides (TMDCs), 2D semiconductor materials, Nano-electronics, Nano-photonics, Materials science
||Synthetic - Chemical Vapour Transport (CVT)
||1020 °C (lit.)
||Metallic Black/dark brown
2D-layered tungsten ditelluride (WTe2) has recently received great research interest for its unique, non-saturating, and extremely large positive magnetoresistance (XMR) behaviour. With perfectly balanced electron-hole populations, this particular non-saturating XMR identified applications for WTe2 in information processing and storage devices.
In ambient conditions, WTe2 crystallises in a orthorhombic lattice - where tungsten atoms are coordinated by tellurium atoms in an octahedral environment. The unit cell contains two Te-W-Te layers (held together by van der Waals interaction), with one sheet rotating 180◦ with respect to the other. This stacking sequence is referred to as a 'distorted 1T (Td) structure'.
Td-WTe2 was the first material proposed to be a type II Weyl semimetal, with a reduced density of states at the Fermi level coming from a small overlap between valence and conduction bands without a band gap. It has been reported that even single and dual-layer WTe2 films preserve the semimetallic nature, and both the films have equal hole and electron carrier concentrations. Additionally, WTe2 has been reported to exhibit pressure-induced superconductivity.
With the distorted 1T (Td) form being thermodynamically-favoured and semi-metal in nature, WTe2 finds applications in pressure-induced superconductivity, memory storage devices, batteries, catalyst, spintronics, and thermo-electric devices.
Tungsten ditelluride (WTe2) is manufactured via chemical vapour transport (CVT) crystallisation, with high purity levels (>99.999%).
Tungsten ditelluride is a great source for obtaining mono- and few-layer WTe2 via mechanical or liquid exfoliation. Single crystals can also be used directly for optical and scanning probe microscopy (such as AFM and TEM studies).
Literature and Reviews
Tungsten Ditelluride: a layered semimetal, C-H. Lee et al., Sci. Rep., 5, 10013 (2015); DOI: 10.1038/srep10013.
Visualizing Type-II Weyl Points in Tungsten Ditelluride by Quasiparticle Interference, C-L. Lin et al., ACS Nano, 11 (11), 11459–11465 (2017);
Three-dimensionality of the bulk electronic structure in WTe2, Y. Wu et al., Phys. Rev. B, 95, 195138 (2017) DOI: 10.1103/PhysRevB.95.195138.,
Electronic Structure Basis for the Extraordinary Magnetoresistance in WTe2, I. Pletikosić et al., Phys. Rev. Lett., 113, 216601 (2014); DIO: 10.1103/PhysRevLett.113.216601.
MoTe2: A Type-II Weyl Topological Metal, Z. Wang et al., Phys. Rev. Lett., 117, 056805 (2016); DOI: 10.1103/PhysRevLett.117.056805.