title: Charge Mediated Reversible Metal-Insulator Transition in Monolayer MoTe2 and WxMo1-xTe2 Alloy.
abstract: Metal-insulator transitions in low-dimensional materials under ambient conditions are rare and worth pursuing due to their intriguing physics and rich device applications. Monolayer MoTe2 and WTe2 are distinguished from other TMDs by the existence of an exceptional semimetallic distorted octahedral structure (T') with a quite small energy difference from the semiconducting H phase. In the process of transition metal alloying, an equal stability point of the H and the T' phase is observed in the formation energy diagram of monolayer WxMo1-xTe2. This thermodynamically driven phase transition enables a controlled synthesis of the desired phase (H or T') of monolayer WxMo1-xTe2 using a growth method such as chemical vapor deposition (CVD) and molecular beam epitaxy (MBE). Furthermore, charge mediation, as a more feasible method, is found to make the T' phase more stable than the H phase and induce a phase transition from the H phase (semiconducting) to the T' phase (semimetallic) in monolayer WxMo1-xTe2 alloy. This suggests that a dynamic metal-insulator phase transition can be induced, which can be exploited for rich phase transition applications in two-dimensional nanoelectronics.
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Santosh
authors.initials: S
authors.lastname: Kc
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Nie
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Chaoping
authors.initials: C
authors.lastname: Liang
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: William G
authors.initials: WG
authors.lastname: Vandenberghe
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Roberto C
authors.initials: RC
authors.lastname: Longo
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Yongping
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Fantai
authors.initials: F
authors.lastname: Kong
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University , Seoul 143-747, Korea.
authors.forename: Suklyun
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.|Department of Physics, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Wallace
authors.affiliation: Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Kyeongjae
authors.initials: K
authors.lastname: Cho
keywords: electrostatic charge; metal−insulator transition; monolayer alloys; reversible phase transition; transition metal dichalcogenides (TMDs); two-dimensional materials