Condensed Matter Seminar Series

Interplay of Strong Electron-Electron and Electron-Boson Interactions in Nanostructures

Kevin Ingersent

University of Florida

Thursday April 28,  11:00 am,  Room 298,  Physics Building

Abstract: In nanostructures such as quantum dots and single-molecule devices, reduced spatial dimensionality enhances the roles of quantum-mechanical interference and of interactions. Electron-electron interactions give rise to the phenomenon of Coulomb blockade, allowing experimental control of electron occupancy within a nanoscopic region (the "dot") weakly connected to external leads. When the electron number is odd, the dot has a residual spin that can undergo collective screening by lead electrons through an analog of the Kondo effect. At the same time, vibrations and other forms of environmental noise act as significant sources of decoherence for the electronic states. This talk will report theoretical studies of the consequences of strong electron-electron and electron-boson coupling in nanostructures. The interplay between these interactions can generate effective attraction between electrons, convert spatially extended spin correlations into long-range charge correlations, and produce quantum (absolute temperature T = 0) phase transitions that should have clear signatures in the electrical transport at T > 0.