Mott insulators
of ultracold alkaline earth fermions : A new class of quantum magnets
Michael Hermele, University of Colorado
A crucial basic property of
antiferromagnetic insulators with SU(2) symmetry is that adjacent spins can
(and tend to) combine to form singlets, or valence bonds. The classical analog
of this fact is that adjacent spins prefer to be antiparallel. These two facts
underly much of our thinking about ground states of quantum antiferromagnets.
Ultracold alkaline earth atoms
can be used to realize magnetic insulators with SU(N) symmetry, where a minimum
of N spins is required to form a singlet, where N can be as large as 10. These
systems belong to a virtually unexplored class of quantum magnets. In this
talk, I will show that even the simplest such models on the square lattice hold
remarkable surprises.