Dual structure in the charge excitation spectrum of electron-doped cuprates

Matias Bejas; Hiroyuki Yamase; Andres Greco

doi:10.1103/physrevb.96.214513

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arXiv · 1709.09468

Dual structure in the charge excitation spectrum of electron-doped cuprates

Matias Bejas·Hiroyuki Yamase·Andres Greco

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Abstract

Motivated by the recent resonant x-ray scattering (RXS) and resonant inelastic x-ray scattering (RIXS) experiments in electron-doped cuprates, we study the charge excitation spectrum in a layered t-J model with the long-range Coulomb interaction. We show that the spectrum is not dominated by a specific type of charge excitations, but by different kinds of charge fluctuations, and is characterized by a dual structure in the energy space. Low-energy charge excitations correspond to various types of bond-charge fluctuations driven by the exchange term (J-term) whereas high-energy charge excitations are due to usual on-site charge fluctuations and correspond to plasmon excitations above the particle-hole continuum. The interlayer coupling, which is frequently neglected in many theoretical studies, is particularly important to the high-energy charge excitations.

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Matias Bejas, Hiroyuki Yamase, Andres Greco. 2017-09-27. Dual structure in the charge excitation spectrum of electron-doped cuprates. https://doi.org/10.1103/physrevb.96.214513

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