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arXiv · 0905.4728

Large-J approach to strongly coupled spin-orbital systems

Gia-Wei Chern·Natalia Perkins
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Abstract

We present a novel approach to study the ground state and elementary excitations in compounds where spins and orbitals are entangled by on-site relativistic spin-orbit interaction. The appropriate degrees of freedom are localized states with an effective angular momentum J. We generalize J to arbitrary large values while maintaining the delicate spin-orbital entanglement. After projecting the inter-site exchange interaction to the manifold of effective spins, a systematic 1/J expansion of the effective Hamiltonian is realized using the Holstein-Primakoff transformation. Applications to representative compounds Sr2IrO4 and particularly vanadium spinels AV2O4 are discussed.

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Gia-Wei Chern, Natalia Perkins. 2009-05-28. Large-J approach to strongly coupled spin-orbital systems. https://doi.org/10.1103/physrevb.80.180409

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