Quantum Institute: Visitor Schedule

The Quantum Lunch is regularly held on Thursdays in the Theoretical Division Conference Room, TA-3, Building 123, Room 121. For more information, contact Diego Dalvit.

February 7 , 2008
Thursday, 12:30 PM to 2 PM

Andrei Chitov,
Brookhaven National Laboratory

Atomic Collapse in Graphene

Abstract

Intercalating graphene with charged impurities, it is possible to model the physics of supercritical heavy relativistic atoms (Z>137) in condensed matter lab. To demonstrate this theoretically, we consider Dirac-like quasiparticles interacting with a Coulomb impurity. We find an infinite family of localized electronic states, when the impurity charge exceeds the critical value Zc=1. These states are related to collapsing relativistic trajectories that descend on the point charge. Klein tunneling couples the localized states to Dirac continuum. Possible signatures of this "atomic collapse" regime in STM measurements and transport properties are discussed.