Fermions, strings, and gauge fields in lattice spin models

Article

关键词: RESONATING-VALENCE-BOND;    HIGH-TC SUPERCONDUCTIVITY;    QUANTUM HALL STATES;    TOPOLOGICAL ORDERS;    PHASE-TRANSITIONS;    EXCITATIONS;    ANTIFERROMAGNETS;    CONFINEMENT;    STATISTICS;   

DOI  :  10.1103/PhysRevB.67.245316

来源: SCIE

【 摘 要 】

We investigate the general properties of lattice spin models with emerging fermionic excitations. We argue that fermions always come in pairs and their creation operator always has a stringlike structure with the newly created particles appearing at the end points of the string. The physical implication of this structure is that the fermions always couple to a nontrivial gauge field. We present exactly soluble examples of this phenomenon in two and three dimensions. Our analysis is based on an algebraic formula that relates the statistics of a lattice particle to the properties of its hopping operators. This approach has the advantage in that it works in any number of dimensions-unlike the flux-binding picture developed in fractional quantum Hall theory.

【 授权许可】

Free