Effect of spin modulation on electronic phase separation in the double exchange model with Coulomb repulsion - art. no. 214402

We investigate the effect of spatial modulation of spin on electronic phase separation (PS) in the double exchange model with Coulomb repulsion and el ectron-phonon coupling. We show that the spatial modulation of the spin-den sity-wave (SDW) state, as well as the paramagnetic state, of e(g) holes has a significant impact on the canted angle in the homogeneous phase and on t he stable hole concentration in the segregated phase. The long-range Coulom b interaction plays an important role in stabilizing the segregated two-pha se state, and we determine the corresponding critical values analytically. We also study the effects of the external magnetic field and of quantum flu ctuation of the SDW order parameter on the PS; our results show that the fo rmer favors but the latter inhibits the PS. We discuss the implications of our results for the perovskite manganites La(1-x)A(x)MnO(3).