] 7 O ct 1 99 9 Spin correlation functions and Néel order in the 2 D Heisenberg model : Effects of spatial anisotropy
نویسنده
چکیده
The ground-state properties of the square-lattice spin-1/2 Heisenberg antiferromagnet with spatially anisotropic couplings are investigated by Green’s-function projection approaches. The staggered magnetization and the two-spin correlators are calculated; the competition between magnetic longand short-range order is discussed in comparison with experiments on Sr2[Ca2]CuO3.
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