%0 Journal Article
%A Li, Z. W.
%A Drees, Y.
%A Kuo, C. Y.
%A Guo, H.
%A Ricci, A.
%A Lamago, D.
%A Sobolev, O.
%A Rütt, U.
%A Gutowski, O.
%A Pi, T. W.
%A Piovano, A.
%A Schmidt, W.
%A Mogare, K.
%A Hu, Z.
%A Tjeng, L. H.
%A Komarek, A. C.
%T Incommensurate spin correlations in highly oxidized cobaltates La$_{2−x}$Sr$_{x}$CoO$_{4}$
%J Scientific reports
%V 6
%@ 2045-2322
%C London
%I Nature Publishing Group
%M FZJ-2016-02829
%P 25117 -
%D 2016
%X We observe quasi-static incommensurate magnetic peaks in neutron scattering experiments on layered cobalt oxides La2−xSrxCoO4 with high Co oxidation states that have been reported to be paramagnetic. This enables us to measure the magnetic excitations in this highly hole-doped incommensurate regime and compare our results with those found in the low-doped incommensurate regime that exhibit hourglass magnetic spectra. The hourglass shape of magnetic excitations completely disappears given a high Sr doping. Moreover, broad low-energy excitations are found, which are not centered at the incommensurate magnetic peak positions but around the quarter-integer values that are typically exhibited by excitations in the checkerboard charge ordered phase. Our findings suggest that the strong inter-site exchange interactions in the undoped islands are critical for the emergence of hourglass spectra in the incommensurate magnetic phases of La2−xSrxCoO4.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000374858800002
%$ pmid:27117928
%R 10.1038/srep25117
%U https://juser.fz-juelich.de/record/809921