A Typology for Quantum Hall Liquids

Speaker: 
Boris Spivak (University of Washington)
Event Date and Time: 
Fri, 2012-02-17 14:00 - 15:00
Location: 
Hennings 318
Local Contact: 
Joshua Folk
Intended Audience: 
Graduate

The Pfaffian phase of electrons in the proximity of a half-filled Landau level is understood to be a p+ip superconductor of composite fermions. We consider the properties of this paired quantum Hall phase when the pairing scale is small, i.e. in the weak-coupling, BCS, limit, where the coherence length is much larger than the charge screening length. We find that, as in a Type I superconductor, the vortices attract so that, upon varying the magnetic field from its magic value at nu = 5/2, the system exhibits a Coulomb frustrated phase separation. We propose that the weakly and strongly coupled Pfaffian states exemplify a general dichotomy between Type I and Type II quantum Hall fluids. At the boundary between Type I and Type II behavior, the Chern-Simons action has a “Bogomol’nyi point,” where the quasi-holes (vortices) are non-interacting.

Website development by Checkmark Media. Designed by Armada.

a place of mind, The University of British Columbia

Faculty of Science
Department of Physics and Astronomy
6224 Agricultural Road
Vancouver, BC V6T 1Z1
Tel 604.822.3853
Fax 604.822.5324

Emergency Procedures | Accessibility | Contact UBC | © Copyright The University of British Columbia