Contrasting Magnetic Behaviors in Rhodium- and Ruthenium-Doped Cubic Perovskite SrFeO3: Nearly Ferromagnetic Metal versus Spin-Glass Insulator.
The effects of Rh and Ru doping for SrFeO3, a helimagnetic metal with a cubic perovskite structure, are studied by magnetic and resistivity measurements. Although SrRhO3is a paramagnetic metal and SrRuO3is a ferromagnetic one, the Rh doping induces a nearly ferromagnetic metallic state, whereas the Ru doping induces a spin-glass insulating state. Mössbauer measurements evidence a marked difference between SrFe0.8Rh0.2O3and SrFe0.8Ru0.2O3in the formal valences of Fe, which are estimated to be 4+ and 3.75+, respectively. The contrasting magnetic behaviors of Rh- and Ru-doped SrFeO3are discussed in terms of the subtle balance between the double-exchange ferromagnetism and the superexchange antiferromagnetism.
Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo, 113-8656, Japan.
Masataka
M
Kinoshita
Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo, 113-8656, Japan.|Department of Physics, Osaka University, Toyonaka, Osaka, 560-0043, Japan.
Hideaki
H
Sakai
Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.|Research Institute for Production Development, Shimogamo-morimoto, Sakyo, Kyoto, 606-0805, Japan.|CREST Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012, Japan.
Naoaki
N
Hayashi
Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo, 113-8656, Japan.|RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan.
Yoshinori
Y
Tokura
Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.|Research Institute for Production Development, Shimogamo-morimoto, Sakyo, Kyoto, 606-0805, Japan.|CREST Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012, Japan.
Mikio
M
Takano
Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo, 113-8656, Japan.|PRESTO Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012, Japan.
Shintaro
S
Ishiwata
ferromagnetism; high-pressure synthesis; magnetic properties; perovskite phases; unusually high valence ions