First-Principles Study of the Magnetic Structure of Na 2 IrO 3

摘要: The iridate Na2IrO3 was proposed to be a realization of the Kitaev model with quantum spin liquid ground state. Experiments have now established that this material hosts zigzag antiferromagnetic order. However, previous assignment ordered moment direction axis is controversial. We examine magnetic using local density approximation plus orbit coupling+U calculations. Our calculations reveal total energy minimized when zigzag-ordered moments are aligned along g≈a+c direction. dependence on directions can explained by adding anisotropic interactions nearest-neighbor Kitaev-Heisenberg model, which spin-wave spectrum also calculated. revision very important understanding and achieving possible exotic electronic phases in compound.