CoFe/FeMn, FeMn/CoFe bilayers and CoFe/FeMn/CoFe trilayers were grown in magnetic field and at room temperature. The exchange bias field Heb depends strongly on the order of depositions and is much higher at CoFe/FeMn than at FeMn/CoFe interfaces. By combining the two bilayer structures into symmetric CoFe/FeMn(tFeMn)/CoFe trilayers, Hebt and Hebb of the top and bottom CoFe layers, respectively, are both enhanced. Reducing tFeMn of the trilayers also results in enhancements of both Hebb and Hebt. These results evidence the propagation of exchange bias between the two CoFe/FeMn and FeMn/CoFe interfaces mediated by the FeMn antiferromagnetic order.
@article{arxiv.0809.2377,
title = {Propagation of Exchange Bias in CoFe/FeMn/CoFe Trilayers},
author = {D. N. H. Nam and W. Chen and K. G. West and D. M. Kirkwood and J. Lu and S. A. Wolf},
journal= {arXiv preprint arXiv:0809.2377},
year = {2009}
}