Superconductivity from site-selective Ru doping studies in Zr₅Ge₃compound

Abstract

Systematical doping studies have been carried out to search for the possible\nsuperconductivity in the transition metal doped Zr$_5$Ge$_3$ system.\nSuperconductivity up to 5.7K is discovered in the Ru-doped\nZr$_5$Ge$_{2.5}$Ru$_{0.5}$ sample. Interestingly, with the same Ru-doping,\nsuperconductivity is only induced with doping at the Ge site, but remains\nabsent down to 1.8K with doping at the Zr site or interstitial site. Both\nmagnetic and transport studies have revealed the bulk superconductivity nature\nfor Ru-doped Zr$_5$Ge$_{2.5}$Ru$_{0.5}$ sample. The high upper critical field,\nenhanced electron correlation, and extremely small electron-phonon coupling,\nhave indicated possible unconventional superconductivity in this system, which\nwarrants further detailed theoretical and experimental studies.\n