Thickness Dependence of Superconductivity in Layered Topological Superconductor β-PdBi(2)

We report a systematic study on the thickness-dependent superconductivity and transport properties in exfoliated layered topological superconductor β-PdBi(2). The superconducting transition temperature T(c) is found to decrease with the decreasing thickness. Below a critical thickness of 45 nm, the superconductivity is suppressed, but followed by an abrupt resistance jump near T(c), which is in opposite to the behavior in a superconductor. We attribute suppressed T(c) to the enhanced disorder as the thickness decreases. The possible physical mechanisms were discussed for the origination of sharply increased resistance in thinner β-PdBi(2) samples.