Magnetic interaction reversal in watermelon nanostructured Cr-doped Fe nanoclusters

• Published in: Applied physics letters Vol. 103; no. 20
• Main Authors: Kaur, Maninder, Dai, Qilin, Bowden, Mark, Engelhard, Mark, Wu, Yaqiao, Tang, Jinke, Qiang, You
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 11.11.2013; American Institute of Physics (AIP)
• Subjects: Antiferromagnetism; Applied physics; Chromium; Chromium oxides; Conversion; Environmental Molecular Sciences Laboratory; Exchange; Intermetallic compounds; Iron; Low concentrations; Magnetism; MATERIALS SCIENCE; Nanoclusters; Nanostructure; Origins; Shells
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4830434

Cr-doped core-shell Fe/Fe-oxide nanoclusters (NCs) were synthesized at varied atomic percentages of Cr from 0 at. % to 8 at. %. The low concentrations of Cr (<10 at. %) were selected in order to inhibit the complete conversion of the Fe-oxide shell to Cr2O3 and the Fe core to FeCr alloy. The magnetic interaction in Fe/Fe-oxide NCs (∼25 nm) can be controlled by antiferromagnetic Cr-dopant. We report the origin of σ-FeCr phase at very low Cr concentration (2 at. %) unlike in previous studies, and the interaction reversal from dipolar to exchange interaction in watermelon-like Cr-doped core-shell NCs.