arXiv:cond-mat/9402001 · Physical review. B, Condensed matter

Chirality operators for Heisenberg spin systems

V. Subrahmanyam

Published Sep 1, 1994• 5 citations

Abstract

The ground state of closed Heisenberg spin chains with an odd number of sites has a chiral degeneracy, in addition to a twofold Kramers degeneracy. A nonzero chirality implies that the spins are not coplanar, and is a measure of handedness. The chirality operator, which can be treated as a spin-1/2 operator, is explicitly constructed in terms of the spin operators, and is given as commutator of permutation operators.

DOI: 10.1103/physrevb.50.6468

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