Fractionalization and Confinement in Frustrated Magnets

[摘要] We study the fractionalization andconfinement of excitations in two frustrated magnets: S = 1/2 kagome Heisenberg antiferromagnet and quantum spin ice. In kagome Heisenberg antiferromagnet, the ground state is a spin liquid that hosts fractional spin excitations known as spinons. We construct a phenomenological theory for the spin liquid state. Our theory explains many characteristic features observed in numerical studies, whereby providing a missing link between theory and numerics. In quantum spin ice, when spinons are confined by an external magnetic field, elementary excitations are strings connecting pairs of spinons. We show that these strings possess quantum dynamics that can be described by an emergent quantum string theory. The vibrational modes of strings are manifested as multiple resonances in dynamical structure factor, which could be observed in experiments.

[发布机构] Johns Hopkins University

[效力级别] spin liquid

[关键词] frustrated magnetism;spin liquid;Physics