Incommensurate spin correlations in highly oxidized cobaltates La2-xSrxCoO4

Z. W. Li, Y. Drees, C. Y. Kuo, H. Guo, A. Ricci, D. Lamago, O. Sobolev, U. Rutt, O. Gutowski, T. W. Pi, A. Piovano, W. Schmidt, K. Mogare, Z. Hu, L. H. Tjeng, A. C. Komarek*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

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.

Original languageEnglish
Article number25117
JournalScientific reports
Volume6
DOIs
StatePublished - 27 Apr 2016

Fingerprint Dive into the research topics of 'Incommensurate spin correlations in highly oxidized cobaltates La<sub>2-x</sub>Sr<sub>x</sub>CoO<sub>4</sub>'. Together they form a unique fingerprint.

Cite this