Positive exchange bias in FeF2-Fe bilayers.
نویسندگان
چکیده
We have discovered a positive unidirectional exchange anisotropy in antiferromagnetic (FeF2) and ferromagnetic (Fe) bilayers cooled through the antiferromagnetic critical temperature TN in large magnetic fields. For low positive cooling fields, the ferromagnet’s magnetization (M-H) loop center shifts to negative fields, as is normally observed in other systems. In contrast, large cooling fields can cause the shift to be positive. This can be explained if the FeF 2 surface spins couple to the external magnetic cooling field above TN and the FeF2-Fe interaction is antiferromagnetic. [S0031-9007 (96)00418-8]
منابع مشابه
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عنوان ژورنال:
- Physical review letters
دوره 76 24 شماره
صفحات -
تاریخ انتشار 1996