At temperatures well below the superconducting transition temperature, thin superconducting wires respond in transport measurements quite similar to Josephson junctions. This behavior can be explained by the occurrence of superconducting quantum phase slips (QPS), which is conceptually dual to the dynamics of Josephson junctions. While in a Josephson junction the superconducting phase difference across a tunnel barrier drives the tunneling of Cooper pairs, the passing of a Cooper pair through a QPS wire is associated with the tunneling of the superconducting phase.
This duality can be studied using the QPS wire as a weak coupling element between two superconductors, e.g. by transport or microwave measurements. We have explored a new possibility of using metallic aluminium-oxide for obtaining a high kinetic inductance, a mandatory ingredient for the QPS effect in wires.
In the talk DC and microwave measurements of aluminium-oxide circuits will be presented.
