Manipulating superconductivity of 1T-TiTe2 by high pressure. Issue 17 (11th April 2017)

• Record Type: Journal Article
• Authors: Xiao, R. C.; Lu, W. J.; Shao, D. F.; Li, J. Y.; Wei, M. J.; Lv, H. Y.; Tong, P.; Zhu, X. B.; Sun, Y. P.
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 17(2017)
• Page Start: 4167
• Page End: 4173
• Publication Date: 2017-04-11
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c7tc00209b
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Superconductivity of transition metal dichalcogenide 1 T -TiTe2 under high pressure was investigated by first-principles calculations. Abstract : Superconductivity of transition metal dichalcogenide 1 T -TiTe2 under high pressure was investigated by first-principles calculations. Our results show that the superconductivity of 1 T -TiTe2 exhibits very different behavior under hydrostatic and uniaxial pressure. The hydrostatic pressure is harmful to the superconductivity, while the uniaxial pressure is beneficial to the superconductivity. The superconducting transition temperature T C at ambient pressure is 0.73 K, and it reduces monotonously under the hydrostatic pressure to 0.32 K at 30 GPa, while T C increases dramatically under the uniaxial pressure along the c axis. The established T C of 6.34 K under the uniaxial pressure of 17 GPa, below which the structural stability is maintained, is above the liquid helium temperature of 4.2 K. The increase of the density of states at the Fermi level, the red-shift of the phonon density of states/Eliashberg spectral function F ( ω )/ α 2 F ( ω ), and the softening of the acoustic modes with pressure are considered as the main reasons that lead to the enhanced superconductivity under uniaxial pressure. In view of the previously predicted topological phase transitions of 1 T -TiTe2 under the uniaxial pressure (Q. Zhang et al., Phys. Rev. B: Condens. Matter Mater. Phys., 2013, 88, 155317), we consider 1 T -TiTe2 as a possible candidate in transition metal chalcogenides for exploring topological superconductivity.