“Flux” State in the Double-Exchange Model

Abstract

We study the ground-state properties of the double-exchange systems. The phase factor of the hopping amplitude arises from the ${t}_{2g}$ spin texture in two or more dimensions. A novel ``flux'' state has a lower energy than the canted antiferromagnetic and spiral spin states. In a certain range of hole doping, a phase separation occurs between the flux state and antiferromagnetic states. Constructing a trial state which provides the rigorous upper bound on the ground state, we show that the metallic canted antiferromagnetic state is not stable in the double-exchange model.