Zhang Wenting, Fang Yuqiang, Zhang Zihan, Tian Fubo, Huang Yanping, Wang Xin, Huang Xiaoli, Huang Fuqiang, Cui Tian
State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China.
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
J Phys Chem Lett. 2021 Apr 8;12(13):3321-3327. doi: 10.1021/acs.jpclett.1c00312. Epub 2021 Mar 26.
High-pressure investigation has been shown to be of paramount significance for changing the conventional lattice or bringing fascinating properties, especially inducing superconducting phases. Here we studied the application of pressure to the recently synthesized 2M-WS with the record (8.8 K) among transition metal dichalcogenides (TMDs) at ambient pressure by electrical resistance investigations, synchrotron X-ray studies, and theoretical calculations. in the initial 2M-WS dropped from the maximum to become undetected, accompanied by a phase transition into a semiconductor, 3R-WS, at 15 GPa. The successive metallization and superconducting transitions in 3R-WS were observed at 48.8 GPa with ≈ 2.5 K. This is the first experimental case in which superconductivity has been realized in the 3R phase among TMDs. We propose that the degradation of superconductivity in 2M-WS and the reemergence of superconductivity in 3R-WS are mainly attributable to changes in the density of states near the Fermi surface driven by the interlayer coupling.
高压研究已被证明对于改变传统晶格或赋予迷人特性至关重要，尤其是诱导超导相。在此，我们通过电阻研究、同步加速器X射线研究和理论计算，研究了对最近合成的2M-WS施加压力的情况，该材料在常压下是过渡金属二硫属化物（TMDs）中具有创纪录超导转变温度（8.8 K）的材料。在初始阶段，2M-WS的超导转变温度从最大值下降直至未被检测到，同时在15 GPa时伴随向半导体3R-WS的相变。在48.8 GPa和转变温度约为2.5 K时观察到3R-WS中连续的金属化和超导转变。这是首次在TMDs的3R相中实现超导性的实验案例。我们认为，2M-WS中超导性的退化以及3R-WS中超导性的重新出现主要归因于层间耦合驱动的费米表面附近态密度的变化。
