ScholarWorks@성균관대학교

초록

LaRu3Si2 is a kagome superconductor with a relatively high superconducting transition temperature of Tc approximate to 7.0 K, making it a promising candidate for exploring the relationship between superconductivity and exotic electronic properties in a kagome lattice. We report on the superconducting properties of LaRu3Si2 through electrical resistivity, heat-capacity, and point-contact spectroscopy measurements. The temperature dependence of the upper critical field and low-temperature electronic specific heat is best described by single s-wave superconductivity. This conclusion is further supported by point-contact spectroscopy results, which, when analyzed by the modified Blonder-Tinkham-Klapwijk model, are consistent with the s-wave superconducting gap A. The evolution of A as a function of temperature and magnetic field follows the behavior characteristic of conventional Bardeen-Cooper-Schrieffer (BCS) superconductors, with a zero-temperature value A(0) of 1.2 meV. The gap-to-Tc ratio 2A(0)/kBTc is 4.27, which is larger than the weak-coupling BCS value of 3.52, indicating that LaRu3Si2 belongs to the family of moderately coupled superconductors. These results can guide future research in understanding the enhancement of Tc and the underlying pairing mechanism in the geometrically frustrated systems.

키워드