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arXiv · 0711.1000

Soft x-ray magnetic circular dichroism study of Ca_1-xSr_xRuO_3 across the ferromagnetic quantum phase transition

J. Okamoto·T. Okane·Y. Saitoh·K. Terai·S. -I. Fujimori·Y. Muramatsu·K. Yoshii·K. Mamiya·T. Koide·A. Fujimori·Z. Fang·Y. Takeda·M. Takano
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Abstract

Ca_1-xSr_xRuO_3, which is ferromagnetic for Sr concentration x > 0.3, has been studied by x-ray magnetic circular dichroism (XMCD) in Ru 3p and O 1s core-level x-ray absorption. XMCD signals appear at x ~ 0.3 and monotonically increases with x in the ferromagnetic phase. While the monotonic increase of the XMCD signals with x is of a typical Stoner-type, the absence of appreciable change in the spectral line shapes of both the Ru 3p and O 1s XMCD spectra indicate that the itinerant-electron ferromagnetism in Ca_1-xSr_xRuO_3 is influenced by strong electron correlation.

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J. Okamoto, T. Okane, Y. Saitoh, K. Terai, S. -I. Fujimori, Y. Muramatsu, K. Yoshii, K. Mamiya, T. Koide, A. Fujimori, Z. Fang, Y. Takeda, M. Takano. 2007-11-20. Soft x-ray magnetic circular dichroism study of Ca_1-xSr_xRuO_3 across the ferromagnetic quantum phase transition. https://doi.org/10.1103/physrevb.76.184441

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