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arXiv · 2307.14885

Spectrum of the hole excitation in spin-orbit Mott insulator Na$_2$IrO$_3$

Wei Wang·Zhao-Yang Dong·Shun-Li Yu·Jian-Xin Li
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Abstract

We study the motion of a hole with internal degrees of freedom, introduced to the zigzag magnetic ground state of Na$_2$IrO$_3$, by using the self-consistent Born approximation. We find that the low, intermediate, and high-energy spectra are primarily attributed to the singlet, triplet, and quintet hole contributions, respectively. The spectral functions exhibit distinct features such as the electron-like dispersion of low-energy states near the $\Gamma$ point, the maximum M-point intensity of mid-energy states, and the hole-like dispersion of high-energy states. These features are robust and almost insensitive to the exchange model and Hund's coupling, and are in qualitative agreement with the angular-resolved photoemission spectra observed in Na$_2$IrO$_3$. Our results reveal that the interference between internal degrees of freedom in different sublattices plays an important role in inducing the complex dispersions.

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Wei Wang, Zhao-Yang Dong, Shun-Li Yu, Jian-Xin Li. 2023-07-27. Spectrum of the hole excitation in spin-orbit Mott insulator Na$_2$IrO$_3$. https://doi.org/10.1088/0256-307x%2F40%2F8%2F087101

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