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arXiv · 1401.2578

Measurement of the spectral line shapes for orbital excitations in the Mott insulator CoO using high-resolution resonant inelastic x-ray scattering

L. Andrew Wray·J. Li·Z. Q. Qiu·Jinsheng Wen·Zhijun Xu·Genda Gu·Shih-Wen Huang·Elke Arenholz·Wanli Yang·Zahid Hussain·Yi-De Chuang
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Abstract

We establish the spectral line shape of orbital excitations created by resonant inelastic X-ray scattering for the model Mott insulator CoO. Improved experimental energy resolution reveals that the line shapes are strikingly different from expectations in a first principles-based atomic multiplet model. Extended theoretical simulations are performed to identify the underlying physical origins, which include a pronounced thermal tail reminiscent of anti-Stokes scattering on the energy gain side of excitations, and an essential contribution from interatomic many-body dynamics on the energy loss side of excitations.

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L. Andrew Wray, J. Li, Z. Q. Qiu, Jinsheng Wen, Zhijun Xu, Genda Gu, Shih-Wen Huang, Elke Arenholz, Wanli Yang, Zahid Hussain, Yi-De Chuang. 2014-01-11. Measurement of the spectral line shapes for orbital excitations in the Mott insulator CoO using high-resolution resonant inelastic x-ray scattering. https://doi.org/10.1103/physrevb.88.035105

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