CAREER: Local Probing of Electron-electron Interactions in Nanostructures

Duke University, Durham NC

Investigators

Abstract

This CAREER project focuses on studying the local mechanisms that govern the behavior of several nanoscale systems under intensive scientific investigation. The project will provide training in the novel scanned probe methods, low temperature instrumentation and nanofabrication methods to the graduate, undergraduate and high school students involved. In particular, scanned probe techniques will be actively implemented, including the novel "scanning gate" microscopy and the scanning capacitance microscopy that are especially suited to study nanostructures. The main directions include: imaging the electron wave functions in quantum dots and a two- dimensional insulator, and studies of electron distribution in carbon nanotubes. The project will enhance understanding of electron-electron interaction phenomena in the nanostructures of active current interest and will significantly develop the novel scanning gate and scanning capacitive microscopy. This CAREER project focuses on studying the local mechanisms that govern the electron-electron interactions in several nanoscale systems under intensive scientific investigation. Scanned probe techniques will be actively implemented, in particular the novel "scanning gate" microscopy and the scanning capacitance microscopy that are especially suited to study nanostructures. The main directions include imaging the electron distribution in quantum dots and a two- dimensional insulator, and studies of electron energy distribution in carbon nanotubes. 1) The electron distribution in a lateral quantum dot will be probed by measuring the electric conductivity through the dot as a biased tip is scanned above the sample surface (scanning gate microscopy). 2) A vertical quantum dot will be induced by the biased tip and scanned inside the heterostucture. 3) Localized electrons in the insulating two-dimensional electron gas will be imaged by the scanning capacitance microscopy. 4) Electron distribution in a carbon nanotube will be locally probed. This project will provide training in the novel scanned probe methods, low temperature instrumentation and microfabrication methods to the graduate, undergraduate and high school students involved.