Strain engineering a 4a×√3a charge-density-wave phase in transition-metal dichalcogenide 1T−VSe2

Published

July 19, 2017

Author(s)

Duming Zhang, Jeonghoon Ha, Hongwoo H. Baek, Yang-Hao Chan, Donat F. Natterer, Alline Myers, Joshua D. Schumacher, William Cullen, Albert Davydov, Young Kuk, Mei-Yin Chou, Nikolai Zhitenev, Joseph A. Stroscio

Abstract

We report a new charge density wave (CDW) structure in strained 1T-VSe2 thin films synthesized by molecular beam epitaxy. The CDW structure is unconventional and exhibits a rectangular 4a×√3a periodicity, as opposed to the previously reported hexagonal 4a×4a structure in bulk crystals. First-principles calculations find both 4a×4a and 4a×√3a structures resulting from soft modes in the phonon dispersion, with the later structure lowered in energy in the presence of strain. A CDW energy gap of 2Δ_"CDW" =(9.1±0.1) "meV" was determined that evolved into a larger metal-insulator gap at temperatures below 500 mK.

Citation

Physical Review Materials

Volume

1

Issue

2

Pub Type

Journals

Download Paper

https://doi.org/10.1103/PhysRevMaterials.1.024005

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Keywords

charge density wave, scanning tunneling microscopy, two-dimensional material, VSe2

Citation

Zhang, D. , Ha, J. , Baek, H. , Chan, Y. , Natterer, D. , Myers, A. , Schumacher, J. , Cullen, W. , Davydov, A. , Kuk, Y. , Chou, M. , Zhitenev, N. and Stroscio, J. (2017), Strain engineering a 4a×√3a charge-density-wave phase in transition-metal dichalcogenide 1T−VSe2, Physical Review Materials, [online], https://doi.org/10.1103/PhysRevMaterials.1.024005, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=920307 (Accessed April 26, 2024)