Nematic phase in the spin one two dimensional anisotropic antiferromagnet

We study quantum phase transitions in the anisotropic Heisenberg model with a pseudodipolar interaction on the square lattice, at zero temperature, using the SU(3) Schwinger boson technique in a mean field approximation. We present the dispersion relation for several values of the parameters. When we take into account the effect of the next near neighbor interaction, the phase diagram, at zero temperature shows the existence of a region in the intermediate frustrated regime, even for zero anisotropy parameter, where the system is magnetically disordered. A prediction of our model is the existence of a finite gap in this region.