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arXiv · 2001.08009

Close inspection of plasmon excitations in cuprate superconductors

Andrés Greco·Hiroyuki Yamase·Matías Bejas
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Abstract

Recently resonant inelastic x-ray scattering experiments reported fine details of the charge excitations around the in-plane momentum ${\bf q}_{\parallel}=(0,0)$ for various doping rates in electron-doped cuprates ${\rm La_{2-x}Ce_xCuO_4}$. We find that those new experimental data are well captured by acoustic-like plasmon excitations in a microscopic study of the layered $t$-$J$ model with the long-range Coulomb interaction. The acoustic-like plasmon is not a usual plasmon typical to the two-dimensional system, but has a small gap proportional to the interlayer hopping $t_z$.

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Andrés Greco, Hiroyuki Yamase, Matías Bejas. 2020-01-22. Close inspection of plasmon excitations in cuprate superconductors. https://doi.org/10.1103/physrevb.102.024509

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