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Physical review. B, Condensed matter

Pseudoscalar chiral long-range order of theS=1/2XYantiferromagnet on the triangular lattice

Sayuri Masui, Donald D. Betts

Published Sep 1, 1993• 2 citations
Publisher

Abstract

We have studied the pseudoscalar chiral long-range order, based on the local operator ${\mathrm{\ensuremath{\chi}}}_{\mathrm{\ensuremath{\psi}}}$=${\mathbf{S}}_{1}$\ensuremath{\cdot}(${\mathbf{S}}_{2}$\ifmmode\times\else\texttimes\fi{}${\mathbf{S}}_{3}$), of the S=1/2 XY antiferromagnet on the triangular lattice. At finite temperature the chirality has been studied via a seventh-order high temperature series expansion of the square of the fluctuation in the pseudoscalar chiral long-range order. An exact diagonalization study on small finite lattices has been used to investigate the chirality long-range order parameter at T=0. While Pad\'e approximant analysis of the series suggests the possibility of a finite-temperature phase transition to a low temperature phase with pseudoscalar chiral long-range order, exact diagonalization results indicate that no such order exists at zero temperature.

DOI
10.1103/physrevb.48.6225

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