Vortex dynamics in a single weak-pinning superconducting channel with a Corbino geometry.

We report transport measurements of vortex flow dynamics in nanofabricated weak-pinning channels of a-NbGe with strong-pinning NbN channel edges. The channels are arranged in circular patterns on a Corbino disk geometry with a radial bias current, thus eliminating the influence of edge barriers to vortex entry on the dynamics. We have developed a SQUID voltmeter arrangement for resolving the flux flow voltage from a small number of vortices moving through such a single mesoscopic channel. We discuss the configuration of this measurement scheme, along with potential applications of this system for measuring the flow of vortices around single weak-pinning channels free from edge barriers.