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Physical Review Letters -- May 1, 2000 -- Volume 84, Issue 18, pp. 4224-4227

Diluted Antiferromagnets in Exchange Bias: Proof of the Domain State Model

P. Miltényi, M. Gierlings, J. Keller, B. Beschoten, and G. Güntherodt

2.Physikalisches Institut, RWTH Aachen, 52056 Aachen, Germany

U. Nowak and K. D. Usadel

Theoretische Tieftemperaturphysik, Gerhard-Mercator-Universität-Duisburg, 47048 Duisburg, Germany

(Received 23 December 1999)

The exchange bias coupling at ferromagnetic/antiferromagnetic interfaces in epitaxially grown Co/CoO layers can intentionally be increased by a factor of up to 3 if the antiferromagnetic CoO layer is diluted by nonmagnetic defects in its volume part away from the interface. Monte Carlo simulations of a simple model of a ferromagnetic layer on a diluted antiferromagnet show exchange bias and explain qualitatively its dilution and temperature dependence. These investigations reveal that diluting the antiferromagnet leads to the formation of volume domains, which cause and control exchange bias. ©2000 The American Physical Society

URL: http://link.aps.org/abstract/PRL/v84/p4224
doi:10.1103/PhysRevLett.84.4224
PACS: 75.70.Cn, 75.40.Mg, 75.50.Lk, 85.70.-w        Additional Information

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