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arXiv · 0706.0634

Room-temperature ferromagnetism in nanoparticles of superconducting materials

Shipra·A. Gomathi·A. Sundaresan·C. N. R. Rao
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Abstract

Nanoparticles of superconducting YBa2Cu3O7-delta (YBCO) (Tc = 91 K) exhibit ferromagnetism at room temperature while the bulk YBCO, obtained by heating the nanoparticles at high temperature (940 degree C), shows a linear magnetization curve. Across the superconducting transition temperature, the magnetization curve changes from that of a soft ferromagnet to a superconductor. Furthermore, our experiments reveal that not only nanoparticles of metal oxides but also metal nitrides such as NbN (Tc = 6 - 12 K) and delta-MoN (Tc ~ 6 K) exhibit room-temperature ferromagnetism.

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Shipra, A. Gomathi, A. Sundaresan, C. N. R. Rao. 2007-06-05. Room-temperature ferromagnetism in nanoparticles of superconducting materials. https://doi.org/10.1016/j.ssc.2007.04.041

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