%0 Journal Article
%T Phase transitions in 2D $J_{1}-J_{2}$ model with arbitrary signs of exchange interactions
%A A. V. Miheyenkov
%A A. V. Shvartsberg
%A A. F. Barabanov
%J Physics
%D 2013
%I arXiv
%X The ground state of the $S=1/2$ $J_{1}-J_{1}$ Heisenberg model on the 2D square lattice with arbitrary signs of exchange constants is considered. States with different spin long-range order types (antiferromagnetic checkerboard, stripe, collinear ferromagnetic) as well as disordered spin-liquid states are described in the frames of one and the same analytical approach. It is shown inter alia, that the phase transition between ferromagnetic spin liquid and long-range order ferromagnet is a second-order one. On the ordered side of the transition the ferromagnetic state with rapidly varying condensate function is detected.
%U http://arxiv.org/abs/1307.6481v1