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arXiv · 1210.4141

Dimensionality controlled Mott transition and correlation effects in single- and bi-layer perovskite iridates

Q. Wang·Y. Cao·J. A. Waugh·S. R. Park·T. F. Qi·O. B. Korneta·G. Cao·D. S. Dessau
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Abstract

We studied Sr2IrO4 and Sr3Ir2O7 using angle-resolved photoemission spectroscopy (ARPES), making direct experimental determinations of intra- and inter-cell coupling parameters as well as Mott correlations and gap sizes. The results are generally consistent with LDA+U+Spin-orbit coupling (SOC) calculations, though the calculations missed the momentum positions of the dominant electronic states and neglected the importance of inter-cell coupling on the size of the Mott gap. The calculations also ignore the correlation-induced spectral peak widths, which are critical for making a connection to activation energies determined from transport experiments. The data indicate a dimensionality-controlled Mott transition in these 5d transition-metal oxides (TMOs).

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Q. Wang, Y. Cao, J. A. Waugh, S. R. Park, T. F. Qi, O. B. Korneta, G. Cao, D. S. Dessau. 2012-10-15. Dimensionality controlled Mott transition and correlation effects in single- and bi-layer perovskite iridates. https://doi.org/10.1103/physrevb.87.245109

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