Spinon confinement and the Haldane gap in SU (n) spin chains

Abstract

We use extensive density-matrix renormalization-group calculations to show that a classification of SU (n) spin chains with regard to the existence of spinon confinement and hence a Haldane gap obtained previously for valence bond solid models applies to SU (n) Heisenberg chains as well. In particular, we observe spinon confinement due to a next-nearest-neighbor interaction in the SU(4) representation 10 chain. © 2009 The American Physical Society.