TY  - JOUR
AU  - Li, Z. W.
AU  - Drees, Y.
AU  - Kuo, C. Y.
AU  - Guo, H.
AU  - Ricci, A.
AU  - Lamago, D.
AU  - Sobolev, O.
AU  - Rütt, U.
AU  - Gutowski, O.
AU  - Pi, T. W.
AU  - Piovano, A.
AU  - Schmidt, W.
AU  - Mogare, K.
AU  - Hu, Z.
AU  - Tjeng, L. H.
AU  - Komarek, A. C.
TI  - Incommensurate spin correlations in highly oxidized cobaltates La$_{2−x}$Sr$_{x}$CoO$_{4}$
JO  - Scientific reports
VL  - 6
SN  - 2045-2322
CY  - London
PB  - Nature Publishing Group
M1  - FZJ-2016-02829
SP  - 25117 -
PY  - 2016
AB  - 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000374858800002
C6  - pmid:27117928
DO  - DOI:10.1038/srep25117
UR  - https://juser.fz-juelich.de/record/809921
ER  -