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Journal of the Physical Society of Japan

Chiral Criticality near Two Dimensions

Hikaru Kawamura

Published Jun 15, 1991• 24 citations
Publisher

Abstract

Critical behavior associated with the helical or noncollinear ordering for isotropic n >3-component spins is studied near d =2 dimensions based on an O ( n )× O (2) nonlinear σ model and the renormalization-group ε= d -2 expansion. A chiral fixed point is found for general n characterized by the critical exponents that are consistent with the previous 1/ n expansion calculation. For n =3, it is argued that because of the nontrivial global topology of the order-parameter space, ∝ 1 ( S O (3))= Z 2 , and the possible existence of a finite-temperature topological transition at d =2, the standard ε= d -2 expansion technique is not applicable.

DOI
10.1143/jpsj.60.1839

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