Zhang Junli, Cao Zhen, He Xin, Liu Wenhao, Wen Yan, Cavallo Luigi, Ren Wencai, Cheng Huiming, Zhang Xixiang
Division of Physical Science and Engineering (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Key Laboratory of Magnetism and Magnetic Materials of the Ministry of Education, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China.
J Phys Chem Lett. 2021 Mar 11;12(9):2219-2225. doi: 10.1021/acs.jpclett.1c00071. Epub 2021 Feb 26.
Two-dimensional (2D) materials have attracted significant attention for their ability to support novel magneto-electrical transport and their optical and magnetic properties, of which their superconductivity is particularly of interest. Here we report on the behavior of superconductivity in 2D MoC crystals when hydrostatic pressure is applied, which has not yet been described in the literature. We found that the localization of boundary atoms disorder-induced Cooper pairs can suppress the superconducting transition temperature () as effectively as a magnetic field and current. We observed that the initially decreased as the pressure increased to 1.75 GPa but then began to increase as the pressure increased further to 2.5 GPa. Our density functional theory calculations revealed that this behavior was linked to the modulation of the strength of the electron-phonon coupling and the electron property, which was triggered by compression of the lattice under high pressure. We attributed the inflection point in the hydrostatic pressure-dependent curve to the structural phase transition of MoC from a hexagonal to an orthorhombic structure. This work presents a new avenue for the study of the superconductivity of MoC, which can be extended to apply to other 2D superconductors to modulate their electronic states.
二维（2D）材料因其支持新型磁电输运的能力及其光学和磁学性质而备受关注，其中其超导性尤为引人关注。在此，我们报道了施加静水压力时二维MoC晶体中的超导行为，这在文献中尚未有描述。我们发现，边界原子无序诱导的库珀对的局域化能够像磁场和电流一样有效地抑制超导转变温度（）。我们观察到，随着压力增加到1.75 GPa，最初下降，但随后随着压力进一步增加到2.5 GPa又开始上升。我们的密度泛函理论计算表明，这种行为与电子 - 声子耦合强度和电子性质的调制有关，这是由高压下晶格压缩引发的。我们将静水压力依赖的曲线中的拐点归因于MoC从六方结构到正交结构的结构相变。这项工作为MoC超导性的研究开辟了一条新途径，可扩展应用于其他二维超导体以调制其电子态。
