Loop bifurcation and magnetization rotation in exchange-biased Ni/FeF2
نویسندگان
چکیده
Justin Olamit,1 Elke Arenholz,2 Zhi-Pan Li,3 Oleg Petracic,3,4 Igor V. Roshchin,3 R. Morales,3,5 Xavier Batlle,3,6 Ivan K. Schuller,3 and Kai Liu1,* 1Physics Department, University of California, Davis, California 95616, USA 2Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA 3Physics Department, University of California–San Diego, La Jolla, California 92093, USA 4Angewandte Physik, University Duisburg-Essen, 47048 Duisburg, Germany 5Departamento de Fisica, Universidad de Oviedo, Oviedo 33007, Spain 6Departament de Física Fonamental, Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain Received 11 October 2004; revised manuscript received 10 January 2005; published 13 July 2005
منابع مشابه
Novel laser-induced dynamics in exchange-biased systems
Ultrafast optical excitation of a ferromagnet/antiferromagnet (Ni/FeF2) exchange bias bilayer produces novel magnetization dynamics unlike ever observed before. An unexpected precession of the magnetization, in reverse magnetic fields that exceed the exchange bias, originates from a reorientation of frustrated spins at the interface. As the laser-excited interface approaches the blocking temper...
متن کاملPositive exchange bias in FeF2-Fe bilayers.
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...
متن کاملRelevance of length scales in exchange biased submicron dots
Strong dot-size dependence of the positive exchange bias onset with the cooling field was found in Ni /FeF2 exchange biased nanostructures. With increasing cooling field, the sign of the exchange bias field changes from negative to coexistence of positive and negative, and eventually to positive. As the structure size decreases, the lower limit of cooling fields necessary for only positive exch...
متن کاملExchange bias and asymmetric reversal in nanostructured dot arrays.
The size dependence of exchange bias field HE and coercivity Hc was studied by measuring exchange biased Fe-FeF2 dot arrays in comparison with an unstructured exchange biased Fe-FeF2 bilayer. The domain sizes in the ferromagnet (FM) and the antiferromagnet (AFM) play an important role for exchange bias (EB), and thus interesting phenomena may be expected when the size of an EB system becomes co...
متن کاملTwo-stage magnetization reversal in exchange biased bilayers.
MnF(2)/Fe bilayers exhibit asymmetric magnetization reversal that occurs by coherent rotation on one side of the loop and by nucleation and propagation of domain walls on the other side of the loop. Here, we show by polarized neutron reflectometry, magnetization, and magnetotransport measurements that for samples with good crystalline "quality" the rotation is a two-stage process, due to cohere...
متن کامل