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تسجيل مستخدم جديدEvolution of charge density wave order and superconductivity under pressure in LaPt$_2$Si$_2$
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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.
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We have studied the superconducting gap structure of LaPt$_2$Si$_2$ by measuring the temperature dependence of the London penetration depth shift $Deltalambda(T)$ and point contact spectroscopy of single crystals. $Deltalambda(T)$ shows an exponentia
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The interplay between charge density wave (CDW) order and superconductivity has attracted much attention. This is the central issue of along standing debate in simple transition metal dichalcogenides without strong electronic correlations, such as 2H
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