Superconductivity in Te-deficient polymorphic MoTe2−x and its derivatives: rich structural and electronic phase transitions. (13th June 2018)

• Record Type: Journal Article
• Authors: Kang, Se Hwang; Yu, Ho Sung; Baik, Jaeyoon; Yang, Heejun; Lee, Young Hee; Cho, Suyeon; Kim, Sung Wng
• Is Part Of: 2D materials. Volume 5:Number 3(2018)
• Publication Date: 2018-06-13
• Subjects: superconductivity -- transition metal dichalcogenide -- polymorphism; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/aac759
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: The group 6 transition metal dichalcogenides (TMDs) have been received great attentions due to intriguing superconducting states correlated with structural uncertainty and electronic complexity. Here, we synthesized Te-deficient polycrystals of semimetallic MoTe2− x and its derivatives (Mo1− y TM y Te2− x Ch x ( TM : Nb, Mn and V, Ch : P)), and investigated the structural and electronic phase transitions. It was found that all Te-deficient semimetallic phases (monoclinic 1T′, hexagonal 2H and rhombohedral 3R) exhibited the superconducting transition, in which 2H and 3R structures were evolved in Nb-substituted Mo1− y Nb y Te2− x (y = 0.4 for 2H, 0.6 for 3R), respectively. Moreover, we found that the superconducting state of 2H-and 3R-Mo1− y Nb y Te2− x appears at the vicinity of the transition from insulator to semimetal regime with the increased electron concentration via TM substitution and Te-deficiency. It is revealed that all superconducting 1T′-, 2H- and 3R-Mo1− y TM y Te2− x Ch x semimetals show the half-dome shaped superconducting phase diagram with respect to the electron concentration and TM substitution.