论文信息 - Enhancement of exchange bias by ultra‐thin Mn layer insertion at the interface of Mn‐Ir/Co‐Fe bilayers

Enhancement of exchange bias by ultra‐thin Mn layer insertion at the interface of Mn‐Ir/Co‐Fe bilayers

Effects of ultra‐thin Mn, Ru, Pd, Ta, Gd, and Tb layer insertion at the interface on the exchange bias of Mn75Ir25/Co70Fe30 bilayers were investigated. Unidirectional anisotropy constant, JK, of the bilayer was significantly enhanced from 0.46 erg/cm2 to 0.84 erg/cm2 with the insertion of 0.5‐nm‐thick Mn layer, while it was reduced with increasing the inserted layer thickness for the other materials. The value of 0.84 erg/cm2 was not obtained in the variation of JK with respect to the chemical composition of Mn‐Ir layer in a range of Ir content of 0 ∼ 40 at.%. The cause of the enhancement of JK with ultra‐thin Mn insertion might be due to the modification of antiferromagnetic spin structure at the interface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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