Reversal behavior of exchange-biased submicron dots
نویسندگان
چکیده
Nanostructured Fe dots were prepared on antiferromagnetic FeF2 thin films and investigated by magneto-optical Kerr effect sMOKEd. We studied the influence of dot sizes on the magnetic hysteresis and compared the result with both continuous thin film bilayers and nanostructured Fe/FeF2 pillars. Hysteresis loops were measured at temperatures below and above s10 and 90 K, respectivelyd the Néel temperature of the antiferromagnet. A vortex state is found for dots of 300 nm diameter, where the exchange bias field is reduced compared to larger dot system and the continuous bilayer. Micromagnetic simulations including the interaction with the antiferromagnet show qualitatively similar behavior. © 2005 American Institute of Physics. fDOI: 10.1063/1.1863449g
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