Magnetotransport Experiments on Fully Metallic Superconducting Dayem-Bridge Field-Effect Transistors

The field effect, as in a field-effect transistor (FET), allows control of the switching current in a metallic superconductor, without affecting the critical temperature or normal-state resistance. Here magnetotransport experiments on Ti-based superconducting FETs reveal several physical insights: The phenomenon occurs at the sample surface, the field effect causes a transition from ballistic to tunnel-like behavior, and a mixed superconducting--normal-metal state is possible at high gate voltages. Such a device could be the cornerstone of easily fabricated monolithic architectures for classical or quantum computing, and a host of other applications in (opto)electronics.