Novel quantum magnetism in Sp(4) and SU(4) spin systems

Speaker: Cenke Xu, Harvard University

When: May 1, 2008 (Thu), 01:30PM to 02:30PM (add to my calendar)
Location: SCI 328

This event is part of the Condensed Matter Theory Seminar Series.

Abstract: We study the quantum phases and quantum phase transitions of Sp(4) and SU(4)
spin systems, with application to spin-3/2 cold atoms. The strong quantum fluctuation of this system leads to many special properties. The Sp(4) Heisenberg model has two independent coefficients, by tuning which the system goes through a deconfined quantum phase transition between the semiclassical magnetic ordered phase and the dimerized phase with strong quantum
fluctuations. A quantum resonating plaquette model was introduced as an effective model of SU(4) Heisenberg systems. The phase diagram of the quantum plaquette model was obtained by a novel gauge field mapping and duality formalism.