A Superconducting Investigation of Nanoscale Mechanics in Niobium Quantum Point Contacts
Research into molecular electronics has exploded in recent years due to a proliferation of new and exciting techniques for producing atomic level structures (e-beam lithography, self-assembled monolayers, etc.); coupling these techniques with the ability to accurately manipulate atomic systems (such as with Scanning Tunneling Microscopes (STM), Atomic Force Microscopes (AFM), or Mechanically Controllable Break Junctions (MCBJ)) opens the possibility to create novel quantum coherent devices for both engineering applications, as well as research into fundamental physics. Along these lines, presented here is a series of experiments on superconducting point contacts which were aimed at understanding the dynamics of coupling superconducting effects to the mechanical degrees of freedom of a nanowire. In addition, another series of experiments presented here explore the nature of charge transport at high biases in superconducting point contacts. Specifically, an investigation of point contacts at high voltage biases revealed a suppression of one component of the total current, which is explained through a phenomenological model.
Advisor:Bruno Frazier; Alexei Marchenkov; Phillip First; Markus Kindermann; Dragomir Davidovic
School:Georgia Institute of Technology
School Location:USA - Georgia
Source Type:Master's Thesis
Date of Publication:06/30/2008