Abstract
AbstractWeyl 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 effects in Weyl semimetals, such as surface Fermi arcs and the chiral anomaly, make them a new playground for exploring novel functionalities. Further exploiting their potential applications requires clear understanding of their topological electronic properties. Here we report a Fourier transform scanning tunneling spectroscopy (FT-STS) study on a type-II Weyl semimetal candidate MoTe2 whose Weyl points are predicated to be located above Fermi level. Although its electronic structure below the Fermi level has been identified by angle resolved photo emission spectroscopy, by comparing our experimental data with first-principles calculations, we are able to identify the origins of multiple scattering channels both below and above Fermi level. Our calculations also show the existence of both trivial and topological arc-like states above the Fermi energy. In the FT-STS experiments, we have observed strong signals from intra-arc scatterings as well as from the scattering between the arc-like surface states and the projected bulk states. A detailed comparison between our experimental observations and calculated results reveals the trivial and non-trivial scattering channels are difficult to distinguish in this compound. Interestingly, we find that the broken inversion symmetry changes the terminating states on the two inequivalent surfaces, which in turn changes the relative strength of the scattering channels observed in the FT-STS images on the two surfaces.
Authors
8
- Davide Iaia (first)
- Guoqing Chang (additional)
- Tay-Rong Chang (additional)
- Jin Hu (additional)
- Zhiqiang Mao (additional)
- Hsin Lin (additional)
- Shichao Yan (additional)
- Vidya Madhavan (additional)
References
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Funders
1
U.S. Department of Energy
10.13039/100000015Region: Americas
gov (National government)
Labels
8- Energy Department
- Department of Energy
- United States Department of Energy
- ENERGY.GOV
- US Department of Energy
- USDOE
- DOE
- USADOE
Awards
2- DE-SC0014335
- DE-SC0014208
@article{Iaia_2018, title={Searching for topological Fermi arcs via quasiparticle interference on a type-II Weyl semimetal MoTe2}, volume={3}, ISSN={2397-4648}, url={http://dx.doi.org/10.1038/s41535-018-0112-5}, DOI={10.1038/s41535-018-0112-5}, number={1}, journal={npj Quantum Materials}, publisher={Springer Science and Business Media LLC}, author={Iaia, Davide and Chang, Guoqing and Chang, Tay-Rong and Hu, Jin and Mao, Zhiqiang and Lin, Hsin and Yan, Shichao and Madhavan, Vidya}, year={2018}, month=aug }