Bismuth kagome sublattice distortions by quenching and flux pinning in superconducting RbBi2

Abstract

The properties of RbBi2, a 4.15 K superconductor, were investigated using magnetic field, pressure, and neutron diffraction. Under hydrostatic pressure, an almost 50% reduction of Tc is observed, linked to a low Debye temperature estimated at 165 K. The resistivity and magnetic susceptibility were measured on quenched and slow-cooled polycrystalline samples. The resistivity follows a low temperature power-law dependence in both types of samples, while the diamagnetic susceptibility, χ, is dependent on the sample cooling history. Slow-cooled samples have χ=-1 while quenched samples have χ