论文标题
水合Lix（H2O）YTAS2的超导性
Superconductivity in hydrated Lix(H2O)yTaS2
论文作者
论文摘要
我们已经系统地研究了超导水合Lix（H2O）YTAS2的结构和物理特性。粉末X射线衍射模式表明所有样品都是单相化合物，晶体结构与2H-TAS2相似。向超导性的过渡温度显示，对锂含量X的圆顶形状依赖性X = 0.42，最大TC为4.6 K，该TC大于没有水或有机插图剂的相应最佳掺杂的2H-TAS2超导体（TC〜4.2 K）。在水合lix（H2O）YTAS2中没有电荷密度波的形成的迹象。尽管我们的磁性数据表明II型行为相当强，但热容量测量结果显示，就像其他2H-TAS2型化合物一样。从相应的Sommerfeld常数和Debye温度，我们可以得出描述电子偶联的参数，以及在费米级的状态DOS（EF）的电子密度作为x的函数。虽然DOS（EF）的变化与TC的变化是一致的，表明锂的插入是通过更改2H-lix（H2O）YTAS2中DOS（EF）调整TC的，但电子偶联和Debye温度的同时变化也可能起到一定作用。
We have systematically studied the structural and physical properties of the superconducting hydrated Lix(H2O)yTaS2. The powder X-ray diffraction patterns suggest that all the samples are single-phase compounds, and the crystal structure is similar to that of 2H-TaS2. The transition temperature to superconductivity shows a dome-shape dependence on the lithium content x with a maximum Tc of 4.6 K for x=0.42, which is larger than in corresponding optimally doped 2H-TaS2 superconductors without water or organic intercalants (Tc ~ 4.2 K). There are no signs for a charge-density-wave formation in hydrated Lix(H2O)yTaS2. While our magnetic data indicate a rather strongly type-II behavior, heat-capacity measurements reveal, like in other 2H-TaS2-type compounds. From the corresponding Sommerfeld constants and Debye temperatures, we can derive the parameter describing the electron-phonon coupling and the electron density of states DOS(EF) at the Fermi level as functions of x. While the variation of the DOS(EF) is consistent with that of Tc, indicating that the lithium intercalation is tuning Tc via changing the DOS(EF) in 2H-Lix(H2O)yTaS2, the simultaneous changes of electron-phonon coupling and Debye temperatures may also play a certain role.
