Frustration in the anisotropic XY model on a triangular lattice

AbstractWe study the XY antiferromagnet with S=1 and single-ion anisotropy on a triangular lattice using the bond operator formalism in two cases: the J1−J2 model, which includes a next-nearest-neighbor coupling J2, and the spatially-anisotropic J1−J1′ model, in which the nearest-neighbor interaction takes a value J1′ along one of the bond directions. The introduction of frustrating second-neighbor interactions leads, at intermediate values of the coupling, to the existence of a disordered phase with the possibility of a quantum liquid behavior. The effect of the frustration on the quantum phase transition is studied. The phase diagrams at T=0 are presented