Type: 
Colloquium
Date-Time: 
Wednesday, October 27, 2010 - 16:00
Location: 
304 Weniger
Event Speaker: 
Brian LeRoy, University of Arizona
Local Contact: 
Ethan Minot
Abstract: 

Note: Special date (Wednesday)

Combining scanning probe microscopy with electrical transport measurements is a powerful approach to probe low-dimensional systems. The local information provided by scanning probe microscopy is invaluable for studying effects such as electron-electron interactions and scattering. Using this approach, we have probed the local electronic properties of graphene. Graphene is a single atomic layer sheet of carbon atoms in a honeycomb lattice. Because of the honeycomb lattice, it has a unique linear dispersion relation and the charge carriers behave as massless fermions. In graphene, we have studied the effect of ripples, charged impurities and defects on the local density of states. We find that long‑range scattering from charged impurities locally shifts the charge neutrality point leading to electron and hole puddles. Recent measurements are able to spatially localize individual charged impurities and understand their effect on the density of states.