论文标题
非静水压力对超导kagome金属CSV $ _3 $ sb $ _5 $的影响
Effect of nonhydrostatic pressure on the superconducting kagome metal CsV$_3$Sb$_5$
论文作者
论文摘要
高压单晶X射线衍射实验表明，超导kagome金属CSV $ _3 $ _3 $ _5 $从六边形（$ p6/mmm $）转变为单胶凝胶（$ c2/m $）在10 GPA以上的对称性（如果非降压条件下），则在二粒含量的情况下与二氧化合物中的含量为硅片，这是对二氧化硅的压力。这与霓虹灯中的准静态条件下的CSV $ _3 $ SB $ _5 $的行为相反，六角形对称性保留至少20 GPA。单斜变形使Kagome平面几乎没有变化，但变形了SB原子的蜂窝网。虽然失真的开始几乎与超导性的重新进入相吻合，但我们的\ textit {ab intibil}密度官能计算显示，与准静态病例相比，电子结构中只有很小的变化。特别是，在单斜型和六边形CSV $ _3 $ _3 $ _5 $ _5 $结构上，在高压下均观察到了由Intayer SB-SB键的形成驱动的费米表面重建，并且可能是重新分入行为的可能原因。
High-pressure single-crystal x-ray diffraction experiments reveal that the superconducting kagome metal CsV$_3$Sb$_5$ transforms from hexagonal ($P6/mmm$) to monoclinic ($C2/m$) symmetry above 10 GPa if nonhydrostatic pressure conditions are created in a diamond anvil cell with silicon oil as pressure-transmitting medium. This is contrary to the behavior of CsV$_3$Sb$_5$ under quasi-hydrostatic conditions in neon, with the hexagonal symmetry retained up to at least 20 GPa. Monoclinic distortion leaves the kagome planes almost unchanged but deforms honeycomb nets of the Sb atoms. While the onset of the distortion almost coincides with the reentrance of superconductivity, our \textit{ab initio} density-functional calculations reveal only minor changes in the electronic structure compared to the quasi-hydrostatic case. In particular, Fermi surface reconstruction driven by the formation of interlayer Sb-Sb bonds is observed in both monoclinic and hexagonal CsV$_3$Sb$_5$ structures at high pressures and comes out as the likely cause for the reentrant behavior.
