Extremely high magnetoresistance and conductivity in the type-II Weyl semimetals WP<sub>2</sub> and MoP<sub>2</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29158479.
- Also identified by DOI 10.1038/s41467-017-01758-z and PMC identifier 5696372.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The peculiar band structure of semimetals exhibiting Dirac and Weyl crossings can lead to spectacular electronic properties such as large mobilities accompanied by extremely high magnetoresistance. In particular, two closely neighboring Weyl points of the same chirality are protected from annihilation by structural distortions or defects, thereby significantly reducing the scattering probability between them. Here we present the electronic properties of the transition metal diphosphides, WP<sub>2</sub> and MoP<sub>2</sub>, which are type-II Weyl semimetals with robust Weyl points by transport, angle resolved photoemission spectroscopy and first principles calculations. Our single crystals of WP<sub>2</sub> display an extremely low residual low-temperature resistivity of 3 nΩ cm accompanied by an enormous and highly anisotropic magnetoresistance above 200 million % at 63 T and 2.5 K. We observe a large suppression of charge carrier backscattering in WP<sub>2</sub> from transport measurements. These properties are likely a consequence of the novel Weyl fermions expressed in this compound.