Roman Sobenes

Major: Chemistry
Mentors: Jack Tregidga, Professor John Harter

MEASURING SUPERCONDUCTIVITY IN STRONTIUM GOLD BISMUTH

The goal of this research is to measure and explore the superconducting properties of strontium gold bismuth (SrAuBi) and barium doped SrAuBi. This research is important because superconductors are vital to make MRI machines, magnetic levitation trains, and Tokamak fusion reactors run, propelling us into a more advanced future. To look into the physical properties of the crystal we used optical and diffraction techniques as well as a scanning electron microscope to characterize the structure, symmetries, and composition of SrAuBi. To measure superconducting properties, we attached a four point probe to the crystals in an argon filled glove box (the crystals are air sensitive). We also measured barium doped SrAuBi to see how doping affects the temperature at which the crystal starts to superconduct, as the barium prevents the crystal structure from puckering under cold temperatures. We confirmed that SrAuBi superconducts at 2.4 Kelvin, but we did not get complete data from the barium doped crystals because the contacts were not perfect. Even so, it seems like they have a lower critical temperature around 2 K, which contradicts past data where the barium actually increased the critical temperature. Further measurements are needed to confirm what effect barium doping and structure has on the superconducting properties of SrAuBi.