Superconductivity in a low carrier density system: A single crystal study of cubic Y$_3$Ru$_4$Ge$_{13}$

TL;DR

This study reports the successful growth and characterization of single crystal Y3Ru4Ge13, a low carrier density cubic superconductor exhibiting multiband superconductivity below 2.85 K, with unusual Hall effect behavior indicating semimetallic properties.

Contribution

First demonstration of single crystal growth and detailed superconducting property analysis of Y3Ru4Ge13, revealing multiband superconductivity in a low carrier density cubic system.

Findings

Superconductivity observed below 2.85 K

Hall coefficient decreases rapidly with temperature

Carrier concentration is 10^20/cm^3, much lower than conventional metals

Abstract

We have successfully grown the single crystal of a low carrier density system Y$_3$Ru$_4$Ge$_{13}$ which crystallizes in the cubic crystal structure with the space group Pm3n. Y$_3$Ru$_4$Ge$_{13}$ exhibits super conductivity below 2.85 K as determined from the electrical resistivity, magnetic susceptibility and heat capacity measurements. The bulk measurements indicate multiband superconductivity in this low carrier system. Hall effect measurements show that the Hall coefficient R$_H$ is positive and it decreases rapidly with temperature which is highly unusual. The simple estimation of the carrier concentration gives a value (\sim 10$^{20}$/cm$^3$) which is 2-3 orders of magnitude lower than that of a conventional metal like Cu which seems to suggest that Y$_3$Ru$_4$Ge$_{13}$ is a semimetal that display multiband superconductivity.