Exploring Low Dimensions: Building Novel Superconducting Nanodevices to Probe New Physics
As nano-electronics approach the 1-dimensional limit, quantum effects begin to dominate their transport properties. These nano-electronics can be used to probe new states of matter as well as create novel devices. However, reaching the size regime where quantum mechanical effects begin to appear is difficult using traditional fabrication techniques. I will present my work on a new method for fabricating devices small enough to probe these boundaries that uses only standard lithographic techniques and allows for precise control over the final size of the nanodevice. In addition, I will describe experimental evidence for Weber blockade, a superconducting vortex dual to Coulomb blockade. When the width of a superconducting wire is on the order of the superconducting coherence length, the wire effectively becomes a one-dimensional quantum dot for vortices. By tuning an external magnetic field and probing the critical current in a superconducting aluminum nanowire, I will show how the entry and exit of a single vortex can be observed and controlled. Understanding and taking advantage of this effect can both lead to more robust small superconducting devices as well as enabling the creation of new devices based on manipulating individual flux quanta.