Díaz-Guerra Viejo, CarlosPérez García, LucasPiqueras De Noriega, Francisco JavierChioncel, M. F.2023-06-202023-06-202009-11-150021-897910.1063/1.3259394https://hdl.handle.net/20.500.14352/44218©) 2009 American Institute of Physics. This work has been supported by MEC through project Nos. MAT2006-01259 and MAT2007-65965-C02-02. High temperature VSM measurements have been carried out at CT-ISOM funded by the Spanish “Ministerio de Ciencia e Innovación.”Magnetic transitions in single-crystal alpha-F_2O_3 (hematite) nanowires, grown by thermal oxidation of iron powder, have been studied in the range of 5-1023 K with a superconducting quantum interference device below room temperature and with a vibrating sample magnetometer at higher temperatures. The broad temperature range covered enables us to compare magnetic transitions in the nanowires with the transitions reported for bulk hematite. Morin temperatures (T-M) of the nanowires and of hematite bulk reference powder were found to be 123 and 263 K, respectively. Also the Neel temperature (T-N) of the nanowires, 852 K, was lower than the bulk T-N value. Measurements of the magnetization as a function of temperature show an enhanced signal in the nanowires, which suggests a decrease in the anti ferromagnetic coupling. A coercive field observed below T-M in the hysteresis loops of the nanowires is tentatively explained by the presence of a magnetic phase.engjournal articlehttp://dx.doi.org/10.1063/1.3259394http://scitation.aip.orgopen access538.9Iron-OxideArraysNanoparticlesFísica de materiales