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arXiv · 0803.2927

Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4

B. J. Kim·Hosub Jin·S. J. Moon·J. -Y. Kim·B. -G. Park·C. S. Leem·Jaeju Yu·T. W. Noh·C. Kim·S. -J. Oh·J. -H. Park·V. Durairaj·G. Cao·E. Rotenberg
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Abstract

We investigated electronic structure of 5d transition-metal oxide Sr2IrO4 using angle-resolved photoemission, optical conductivity, and x-ray absorption measurements and first-principles band calculations. The system was found to be well described by novel effective total angular momentum Jeff states, in which relativistic spin-orbit (SO) coupling is fully taken into account under a large crystal field. Despite of delocalized Ir 5d states, the Jeff-states form so narrow bands that even a small correlation energy leads to the Jeff = 1/2 Mott ground state with unique electronic and magnetic behaviors, suggesting a new class of the Jeff quantum spin driven correlated-electron phenomena.

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B. J. Kim, Hosub Jin, S. J. Moon, J. -Y. Kim, B. -G. Park, C. S. Leem, Jaeju Yu, T. W. Noh, C. Kim, S. -J. Oh, J. -H. Park, V. Durairaj, G. Cao, E. Rotenberg. 2008-03-20. Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4. https://doi.org/10.1103/physrevlett.101.076402

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