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arXiv:cond-mat/9911119 · Physical review. B, Condensed matter

Spin-Peierls transition in an anisotropic two-dimensional XY model

Qingshan Yuan, Yumei Zhang, Hong Chen

Published Jun 14, 2001• 8 citations
arXivHTMLPDF

Abstract

The two-dimensional Jordan-Wigner transformation is used to investigate the zero-temperature spin-Peierls transition for an anisotropic two-dimensional $\mathrm{XY}$ model in the adiabatic limit. The phase diagram between the dimerized (D) state and uniform (U) state is shown in the parameter space of dimensionless interchain coupling $h{(=J}_{\ensuremath{\perp}}/J)$ and spin-lattice coupling \ensuremath{\eta}. It is found that the spin-lattice coupling $\ensuremath{\eta}$ must exceed some critical value ${\ensuremath{\eta}}_{c}$ in order to reach the D phase for any finite h. The dependence of ${\ensuremath{\eta}}_{c}$ on h is given by $\ensuremath{-}1/\mathrm{ln}h$ for $\stackrel{\ensuremath{\rightarrow}}{h}0$ and the transition between the U and D phases is of first order for at least $h>{10}^{\ensuremath{-}3}.$

DOI
10.1103/physrevb.64.012414

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