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

Qingshan Yuan·Yumei Zhang·Hong Chen
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Abstract

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

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Qingshan Yuan, Yumei Zhang, Hong Chen. 2001-09-24. Spin-Peierls transition in an anisotropic two-dimensional XY model. https://doi.org/10.1103/physrevb.64.012414

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