Thickness Dependence of Superconductivity in Layered Topological Superconductor beta-PdBi2

We report a systematic study on the thickness-dependent superconductivity and transport properties in exfoliated layered topological superconductor beta-PdBi2. 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 beta-PdBi2 samples.