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arXiv · 1608.05092

Quenched Magnon excitations by oxygen sublattice reconstruction in (SrCuO$_2$)$_n$/(SrTiO$_3$)$_2$ superlattices

M. Dantz·J. Pelliciari·D. Samal·V. Bisogni·Y. Huang·P. Olalde-Velasco·V. N. Strocov·G. Koster·T. Schmitt
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Abstract

The recently discovered structural reconstruction in the cuprate superlattice (SrCuO$_2$)$_n$/(SrTiO$_3$)$_2$ has been investigated across the critical value of $n=5$ using resonant inelastic x-ray scattering (RIXS). We find that at the critical value of $n$, the cuprate layer remains largely in the bulk-like two-dimensional structure with a minority of Cu plaquettes being reconstructed. The partial reconstruction leads to quenching of the magnons starting at the $\Gamma$-point due to the minority plaquettes acting as scattering points. Although comparable in relative abundance, the doped charge impurities in electron-doped cuprate superconductors do not show this quenching of magnetic excitations.

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M. Dantz, J. Pelliciari, D. Samal, V. Bisogni, Y. Huang, P. Olalde-Velasco, V. N. Strocov, G. Koster, T. Schmitt. 2016-08-17. Quenched Magnon excitations by oxygen sublattice reconstruction in (SrCuO$_2$)$_n$/(SrTiO$_3$)$_2$ superlattices. https://doi.org/10.1038/srep32896

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