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Progress of Theoretical Physics Supplement

Disordered Phases in Mixed Quantum Spin Chains

Ken'ichi Takano

Published Jan 1, 2002• 0 citations
Publisher

Abstract

Mixed quantum spin chains with periodicity are transformed into a nonlinear σ model (NLSM). The NLSM deduces a general formula which determines whether the system has a spin gap or not. The formula is applied to some concrete systems and their ground-state phase diagrams are derived. The odd period case is generally discussed.
DOI
10.1143/ptps.145.170

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