Showing 1–1 of 1 results for author: Sacco, C

Gapped collective charge excitations and interlayer hopping in cuprate superconductors

Authors: M. Hepting, M. Bejas, A. Nag, H. Yamase, N. Coppola, D. Betto, C. Falter, M. Garcia-Fernandez, S. Agrestini, K. -J. Zhou, M. Minola, C. Sacco, L. Maritato, P. Orgiani, H. I. Wei, K. M. Shen, D. G. Schlom, A. Galdi, A. Greco, B. Keimer

Abstract: We use resonant inelastic x-ray scattering (RIXS) to probe the propagation of plasmons in the electron-doped cuprate superconductor Sr$_{0.9}$La$_{0.1}$CuO$_2$ (SLCO). We detect a plasmon gap of $\sim$~120 meV at the two-dimensional Brillouin zone center, indicating that low-energy plasmons in SLCO are not strictly acoustic. The plasmon dispersion, including the gap, is accurately captured by laye… ▽ More We use resonant inelastic x-ray scattering (RIXS) to probe the propagation of plasmons in the electron-doped cuprate superconductor Sr$_{0.9}$La$_{0.1}$CuO$_2$ (SLCO). We detect a plasmon gap of $\sim$~120 meV at the two-dimensional Brillouin zone center, indicating that low-energy plasmons in SLCO are not strictly acoustic. The plasmon dispersion, including the gap, is accurately captured by layered $t$-$J$-$V$ model calculations. A similar analysis performed on recent RIXS data from other cuprates suggests that the plasmon gap is generic and its size is related to the magnitude of the interlayer hopping $t_z$. Our work signifies the three-dimensionality of the charge dynamics in layered cuprates and provides a new method to determine $t_z$. △ Less

Submitted 28 June, 2022; originally announced June 2022.

Comments: 17 pages, 10 figures, includes Supplemental Material. Accepted for publication in Physical Review Letters

Journal ref: Phys. Rev. Lett. 129, 047001 (2022)