Current-phase Relationship, Thermal and Quantum Phase Slips in Superconducting Nanowires made on Scaffold Created using Adhesive Tape

摘要

Quantum phase slippage (QPS) in a superconducting nanowire is a new candidatefor developing a quantum bit. It has also been theoretically predicted that theoccurrence of QPS significantly changes the current-phase relationship (CPR) ofthe wire due to the tunneling between topologically different metastablestates. We present studies on the microwave response of the superconductingnanowires to reveal their CPRs. First, we demonstrate a simple nanowirefabrication technique, based on commercially available adhesive tapes, whichallows making thin superconducting wire from different metals. We compare theresistance vs. temperature curves of Mo$_{76}$Ge$_{24}$ and Al nanowires to theclassical and quantum models of phase slips. In order to describe theexperimentally observed microwave responses of these nanowires, we use theMcCumber-Stewart model, which is generalized to include either classical orquantum CPR.