Absence Of Andreev Bound States In Beta-Pdbi2 Probed By Point-Contact Andreev Reflection Spectroscopy

We report point-contact spectroscopic studies on high quality single crystalline beta-PdBi2 with a superconducting T-c = 5.2 K. Our measurements showa typical double-peak structure in the voltage-biased junction conductance at low temperatures, probably excluding the existence of topological Andreev bound states. The conductance curves can be well fitted with the standard Blonder-Tinkham-Klapwijk model for s-wave superconductors, yielding a superconducting gap Delta(0) similar or equal to 0.92 meV with 2 Delta(0)/k(B)T(c) similar to 4.1. Our results strongly suggest that beta-PdBi2 is a conventional intermediate-coupling s-wave superconductor.