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arXiv · 0906.2539

Subtlety of Determining the Critical Exponent $ν$ of the Spin-1/2 Heisenberg Model with a Spatially Staggered Anisotropy on the Honeycomb Lattice

F. -J. Jiang·U. Gerber
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Abstract

Puzzled by the indication of a new critical theory for the spin-1/2 Heisenberg model with a spatially staggered anisotropy on the square lattice as suggested in \cite{Wenzel08}, we study a similar anisotropic spin-1/2 Heisenberg model on the honeycomb lattice. The critical point where the phase transition occurs due to the dimerization as well as the critical exponent $ν$ are analyzed in great detail. Remarkly, using most of the available data points in conjunction with the expected finite-size scaling ansatz with a sub-leading correction indeed leads to a consistent $ν= 0.691(2)$ with that calculated in \cite{Wenzel08}. However by using the data with large number of spins $N$, we obtain $ν= 0.707(6)$ which agrees with the most accurate Monte Carlo O(3) value $ν= 0.7112(5)$ as well.

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F. -J. Jiang, U. Gerber. 2009-09-01. Subtlety of Determining the Critical Exponent $ν$ of the Spin-1/2 Heisenberg Model with a Spatially Staggered Anisotropy on the Honeycomb Lattice. https://doi.org/10.1088/1742-5468%2F2009%2F09%2Fp09016

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