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Anisotropy-induced ordering in the quantum J1-J2 antiferromagnet

Tommaso Roscilde·Adrian Feiguin·Alexander L. Chernyshev·Shiu Liu·Stephan Haas
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Abstract

We study the effect of spin anisotropies on a frustrated quantum antiferromagnet using the J_1-J_2^{XXZ} model on the square lattice. The T=0 and finite-T phase diagrams of this model are obtained utilizing spin-wave theory, exact diagonalization, and quantum Monte Carlo. We find that anisotropic frustration tends to stabilize XY- and Ising-like ordered phases, while the disordered spin-liquid phase is restricted to a small region of the phase diagram. The ordered phases are separated by first-order transitions and exhibit a non-trivial reentrance phenomenon.

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Tommaso Roscilde, Adrian Feiguin, Alexander L. Chernyshev, Shiu Liu, Stephan Haas. 2004-03-16. Anisotropy-induced ordering in the quantum J1-J2 antiferromagnet. https://doi.org/10.1103/physrevlett.93.017203

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