Quantum Order by Disorder in Frustrated Diamond Lattice Antiferromagnets
Jan 31, 2008
3:00PM to 4:00PM
Date/Time
Date(s) - 31/01/2008
3:00 pm - 4:00 pm
Title: Quantum Order by Disorder in Frustrated Diamond Lattice Antiferromagnets
Speaker: Mr. Jean-Sebastien Bernier
Institute: University of Toronto
Location: BSB-106
Description:
We present a quantum theory of frustrated diamond lattice antiferromagnets. Considering quantum fluctuations as the predominant mechanism relieving spin frustration, we find a rich phase diagram comprising of six phases with coplanar spiral ordering in addition to the Neel phase. By computing the specific heat of these ordered phases, we obtain a remarkable agreement between (k,k,0)-spiral ordering and the experimental specific heat data for the diamond lattice spinel compounds CoRh2O4, Co3O4 and MnSc2S4. Consequently, specific heat data is a strong evidence for (k,k,0)-spiral ordering in all of these materials. Based on this agreement, we infer a monotonically increasing relationship between frustration and the strength of quantum fluctuations.