论文标题
电荷密度波订单的演变和在压力下的超导性的演变
Evolution of charge density wave order and superconductivity under pressure in LaPt$_2$Si$_2$
论文作者
论文摘要
我们报告了在压力下的单晶电阻率$ _2 $ _2 $的电阻率和交流磁化易感性的测量，以研究超导性和CDW顺序的相互作用。 LAPT $ _2 $ si $ _2 $表现出从四方到正交结构的一阶相过渡，并伴随着CDW订单以下的CDW订单发作$ t _ {\ rm {cdw}} $ = 76 k最初会抑制CDW过渡，但增强了$ t _ {\ rm {c}} $。在2.4 GPA以上的压力下，CDW订单消失，而$ t _ {\ rm {c}} $和电阻率$ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a $ a则在此压力周围达到了最大值。我们的结果表明，在BCS理论的框架内，可以考虑超导圆顶的发生，在CDW间隙闭合时，状态密度最大。
We report measurements of the electrical resistivity and ac magnetic susceptibility of single crystalline LaPt$_2$Si$_2$ under pressure, in order to investigate the interplay of superconductivity and CDW order. LaPt$_2$Si$_2$ exhibits a first order phase transition from a tetragonal to orthorhombic structure, accompanied by the onset of CDW order below $T_{\rm{CDW}}$ = 76 K, while superconductivity occurs at a lower temperature of $T_{\rm{c}}$ = 1.87 K. We find that the application of pressure initially suppresses the CDW transition, but enhances $T_{\rm{c}}$. At pressures above 2.4 GPa, CDW order vanishes, while both $T_{\rm{c}}$ and the resistivity $A$-coefficient reach a maximum value around this pressure. Our results suggest that the occurrence of a superconducting dome can be accounted for within the framework of BCS theory, where there is a maximum in the density of states upon the closure of the CDW gap.
