Condensed-Matter Physics & Materials Science Seminar

"Giant flavor-Hall effect and nonlocal transport in Dirac materials"

Presented by Dmitry Abanin, Princeton University

Thursday, December 2, 2010, 11:00 am — Small seminar room, Bldg. 510

Dirac materials, graphene and topological insulators, provide a unique opportunity to explore quantum-relativistic phenomena in a condensed matter laboratory. Interesting phenomena associated with the internal degrees of freedom, spin and valley, including quantum spin-Hall effect, have been theoretically proposed, but could not be observed so far largely due to disorder and density inhonogeneity. We show that weak magnetic field breaks the symmetries that protect flavor (spin, valley) degeneracy, and induces large bulk non-quantized flavor-Hall effect in graphene. The effect occurs due to flavor splitting which generates the imbalance of the Hall resistivities of the two flavor species. At the Dirac point, flavor-Hall effect is greatly enhanced due to anomalous magnetotransport of Dirac-like carriers. The flavor-Hall effect is robust in the presence of disorder and interactions, and can serve as a hallmark of the quasi-relativistic carriers in the system. It manifests itself in large nonlocal transport mediated by long-lived flavor currents, as well as in flavor injection and
accumulation experiments. Recent experimental observation of the giant
nonlocal transport in graphene following our prediction opens up
new opportunities for creating and manipulating flavor currents. Our work shows that nonlocal electric transport provides a tool to study neutral modes in solid-states systems.

Hosted by: Robert Konik

6947  |  INT/EXT  |  Events Calendar

 

Not all computers/devices will add this event to your calendar automatically.

A calendar event file named "calendar.ics" will be placed in your downloads location. Depending on how your device/computer is configured, you may have to locate this file and double click on it to add the event to your calendar.

Event dates, times, and locations are subject to change. Event details will not be updated automatically once you add this event to your own calendar. Check the Lab's Events Calendar to ensure that you have the latest event information.