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arXiv · 1608.03306

Auxiliary fermion approach to the RIXS spectrum in a doped cuprate

Yifei Shi·Andrew James·Eugene Demler·Israel Klich
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Abstract

We describe a method for calculating the resonant inelastic X-ray scattering (RIXS) response---including the dynamics of the transient core hole---of many-body systems with non-trivial gap structure encoded in their single particle Green's function. Our approach introduces auxiliary fermions in order to obtain a form amenable to the determinant method of Benjamin et al. [PRL 112 247002 (2014)], and is applicable to systems where interactions are most strongly felt through a renormalization of the single particle propagator. As a test case we consider the Yang Rice Zhang ansatz describing cuprate phenomena in the underdoped `pseudogap' regime, and show that including the core hole dynamics pushes the RIXS peaks towards higher energy transfer, improving agreement with experiments.

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Yifei Shi, Andrew James, Eugene Demler, Israel Klich. 2016-08-10. Auxiliary fermion approach to the RIXS spectrum in a doped cuprate. https://doi.org/10.1103/physrevb.96.155101

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