Abstract
The composition dependence of the structural transition between the monoclinic 1T′ and orthorhombic Td phases in the Mo1-xWxTe2 Weyl semimetal was investigated by elastic neutron scattering on single crystals up to x≈0.54. First observed in MoTe2, the transition from Td to 1T′ is accompanied by an intermediate pseudo-orthorhombic phase, Td∗. Upon doping with W, the Td∗ phase vanishes by x≈0.34. Above this concentration, a phase coexistence behavior with both Td and 1T′ is observed instead. The interlayer in-plane positioning parameter δ, which relates to the 1T′β angle, decreases with temperature as well as with W substitution, likely due to strong anharmonicity in the interlayer interactions. The temperature width of the phase coexistence remains almost constant up to x≈0.54, in contrast to the broadening reported under pressure.
| Original language | English |
|---|---|
| Article number | 054105 |
| Journal | Physical Review B |
| Volume | 102 |
| Issue number | 5 |
| DOIs | |
| State | Published - Aug 1 2020 |
Funding
This work has been supported by the Department of Energy, Grant No. DE-FG02-01ER45927. A portion of this research used resources at the High Flux Isotope Reactor and the Spallation Neutron Source, which are DOE Office of Science User Facilities operated by Oak Ridge National Laboratory. We acknowledge the support of the National Institute of Standards and Technology, US Department of Commerce, in providing the neutron research facilities used in this work. This paper has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this paper, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). Utilization of the FEI Quanta LV200 Environmental Scanning Electron Microscope instrument within UVa's Nanoscale Materials Characterization Facility (NMCF) was fundamental to this work, and I acknowledge the assistance of Richard White for equipment training and analysis of the data.