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arXiv · 0910.4377

Optical spectroscopic investigation on the temperature-dependent electronic structure evolution of the Jeff,1/2 Mott insulator Sr2IrO4

S. J. Moon·Hosub Jin·W. S. Choi·J. S. Lee·S. S. A. Seo·J. Yu·G. Cao·T. W. Noh·Y. S. Lee
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Abstract

We investigated the temperature-dependent evolution of the electronic structure of the Jeff,1/2 Mott insulator Sr2IrO4 using optical spectroscopy. The optical conductivity spectra $σ(ω)$ of this compound has recently been found to exhibit two d-d transitions associated with the transition between the Jeff,1/2 and Jeff,3/2 bands due to the cooperation of the electron correlation and spin-orbit coupling. As the temperature increases, the two peaks show significant changes resulting in a decrease in the Mott gap. The experimental observations are compared with the results of first-principles calculation in consideration of increasing bandwidth. We discuss the effect of the temperature change on the electronic structure of Sr2IrO4 in terms of local lattice distortion, excitonic effect, electron-phonon coupling, and magnetic ordering.

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S. J. Moon, Hosub Jin, W. S. Choi, J. S. Lee, S. S. A. Seo, J. Yu, G. Cao, T. W. Noh, Y. S. Lee. 2009-10-22. Optical spectroscopic investigation on the temperature-dependent electronic structure evolution of the Jeff,1/2 Mott insulator Sr2IrO4. https://arxiv.org/abs/0910.4377

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