Presentation Information
[1P39]Effects of Ar+ beam irradiation on the Incommensurate-Nearly commensurate CDW phase transitions in thin-layer TaS2
*Yoshinao Ikeno1, Takumi Yoshida1, Yuya Miyake2, Satoru Konabe1,2, Kazuyuki Takai1,2 (1. Department of Applied Chemistry, Graduate school of Science and Engineering, Hosei University, 2. Department of Chemical Science and Technology, Hosei University)
Thin-layer tantalum disulfide (TaS2), a metallic two-dimensional material, exhibits the charge density wave (CDW) phase transitions between the nearly commensurate (NCCDW) and incommensurate (ICCDW) phases with temperature hysteretic in the temperature dependence of the electrical resistance, of which the transition differs from that of the bulk crystal. However, the role of the defects remains unknown in the transition of thin-layer TaS2. We quantitatively introduced defects into thin-layer 1T-TaS2 by Ar+ beam irradiation and assessed their effects on its CDW phase transitions. The temperature hysteresis width (ΔT) of the resistivity for 1T-TaS2 (ca. 22 layers) upon the phase transition decreased with increasing irradiation dose. This is explained by the reduction of the barrier potential between two phases caused by an increase in the anharmonicity in the lattice system, where the electron doping by the presence of sulfur vacancies introduced by ion beam irradiation is responsible.