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arXiv · 1507.00658

The Insulating Nature of Na2IrO3: Mott-type or Slater-type?

Minjae Kim·Beom Hyun Kim·B. I. Min
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Abstract

We have investigated temperature-dependent electronic structures of Na2IrO3 to unravel its insulating nature. Employing the combined scheme of the density-functional theory (DFT) and the dynamical mean-field theory (DMFT), we have shown that the insulating state persists even above the Neel temperature (T_{N}), which reveals that Na2IrO3 is classified into a Mott-type insulator. The measured photoemission spectrum in the paramagnetic (PM) state is well described by the electronic structure obtained from the DFT+DMFT for the insulating state above T_{N}. The analysis of optical conductivity, however, suggests that the non-local correlation effect is also important in Na2IrO3. Therefore, Na2IrO3 is not to be a standard Mott insulator in that the extended nature and the non-local correlation effect of Ir 5d electrons are important as well in describing its electronic and magnetic properties.

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Minjae Kim, Beom Hyun Kim, B. I. Min. 2015-07-02. The Insulating Nature of Na2IrO3: Mott-type or Slater-type?. https://doi.org/10.1103/physrevb.93.195135

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