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arXiv · 0808.2743

The ground-state magnetic ordering of the spin-1/2 frustrated J1-J2 XXZ model on the square lattice

R. Darradi·J. Richter·J. Schulenburg·R. F. Bishop·P. H. Y. Li
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Abstract

Using the coupled-cluster method for infinite lattices and the exact diagonalization method for finite lattices, we study the influence of an exchange anisotropy Delta on the ground-state phase diagram of the spin-1/2 frustrated J1-J2 XXZ antiferromagnet on the square lattice. We find that increasing Delta>1 (i.e. an Ising type easy-axis anisotropy) as well as decreasing Delta<1 (i.e. an XY type easy-plane anisotropy) both lead to a monotonic shrinking of the parameter region of the magnetically disordered quantum phase. Finally, at Delta~1.9 this quantum phase disappears, whereas in pure XY limit (Delta=0) there is still a narrow region around J2 =0.5J1 where the quantum paramagnetic ground-state phase exists.

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R. Darradi, J. Richter, J. Schulenburg, R. F. Bishop, P. H. Y. Li. 2008-09-15. The ground-state magnetic ordering of the spin-1/2 frustrated J1-J2 XXZ model on the square lattice. https://doi.org/10.1088/1742-6596/145/1/012049

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