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arXiv · 1612.01019

Experimental signatures of phase interference and sub-femtosecond time dynamics on the incident energy axis of resonant inelastic X-ray scattering

L. Andrew Wray·Shih-Wen Huang·Yuqi Xia·M. Zahid Hasan·Charles Mathy·Hiroshi Eisaki·Zahid Hussain·Yi-De Chuang
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Abstract

Core hole resonance is used in X-ray spectroscopy to incisively probe the local electronic states of many-body systems. Here, resonant inelastic X-ray scattering (RIXS) is studied as a function of incident photon energy on Mott insulators SrCuO2 and NiO to examine how resonance states decay into different excitation symmetries at the transition metal M-, L- and K-edges. Quantum interference patterns characteristic of the two major RIXS mechanisms are identified within the data, and used to distinguish the attosecond scale scattering dynamics by which fundamental excitations of a many-body system are created. A function is proposed to experimentally evaluate whether a particular excitation has constructive or destructive interference in the RIXS cross-section, and corroborates other evidence that an anomalous excitation is present at the leading edge of the Mott gap in quasi-one dimensional SrCuO2.

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L. Andrew Wray, Shih-Wen Huang, Yuqi Xia, M. Zahid Hasan, Charles Mathy, Hiroshi Eisaki, Zahid Hussain, Yi-De Chuang. 2016-12-03. Experimental signatures of phase interference and sub-femtosecond time dynamics on the incident energy axis of resonant inelastic X-ray scattering. https://doi.org/10.1103/physrevb.91.035131

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