Carrier-induced noncollinear magnetism in perovskite manganites by first-principles calculations

We have performed noncollinear first-principles density-functional calculations of carrier-doped perovskite manganites La1-xSrxMnO3 (0.0≤x≤1.0). In the calculated magnetic phase diagram (T = 0) within the collinear magnetic configurations, ferromagnetic and several antiferromagnetic configurations successively appeared as a ground state with increasing x. The calculated total energies of the ferromagnetic and A-type antiferromagnetic phases are almost degenerate around the phase boundary, x 0.5. We found that the noncollinear magnetic configurations are stable in a wide range of carrier concentrations 0.3≤x≤0.6. We discuss the effect of lattice distortions on the stability of the noncollinear magnetic phase.