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arXiv · 1408.6314

Correlated vs. conventional insulating behavior in the Jeff=1/2 vs. 3/2 bands in the layered iridate Ba2IrO4

M. Uchida·Y. F. Nie·P. D. C. King·C. H. Kim·C. J. Fennie·D. G. Schlom·K. M. Shen
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Abstract

We employ molecular beam epitaxy to stabilize Ba2IrO4 thin films and utilize in situ angle-resolved photoemission spectroscopy to investigate the evolution of its electronic structure through the Neel temperature TN. Our measurements indicate that dispersions of the relativistic Jeff=1/2 and 3/2 bands exhibit an unusual dichotomy in their behavior through the Neel transition. Although the charge gap survives into the paramagnetic state, only the Jeff=1/2 state exhibits a strong temperature dependence and its gap softens with increasing temperature approaching TN, while the nearly fully occupied Jeff=3/2 state which remains nearby in energy exhibits negligible changes with temperature.

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M. Uchida, Y. F. Nie, P. D. C. King, C. H. Kim, C. J. Fennie, D. G. Schlom, K. M. Shen. 2014-08-27. Correlated vs. conventional insulating behavior in the Jeff=1/2 vs. 3/2 bands in the layered iridate Ba2IrO4. https://doi.org/10.1103/physrevb.90.075142

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