Abstract
We report an extensive structural characterization of the surface of 1T-PtTe2 crystals by means of helium atom scattering (HAS) and ultra-high resolution scanning tunnelling microscopy (STM). HAS reveals that this bi-dimensional surface presents a large structural corrugation (∼0.33 Å) in ΓM̄ direction. The surface lattice constant of PtTe2 derived from the positions of the helium diffraction peaks up to fifth order was found to be a = (3.96 ± 0.05) Å, in agreement with STM and x-ray diffraction measurements. This value remains unchanged in the temperature range between 90 and 580 K. These findings suggest that 1T-PtTe2 behaves similarly to graphene on a weakly-interacting substrate, for which the surface thermal expansion coefficient is zero within experimental error. The electron-phonon coupling constant λ has been determined by recording the thermal attenuation of the elastic diffraction peaks of PtTe2. Based on a recently developed quantum theoretical method adapted to layered degenerate semiconductors we find that λ lies between 0.38-0.42.
Original language | English |
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Article number | 025007 |
Journal | 2D Materials |
Volume | 7 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2020 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering