Exchange couplings in magnetic films

Abstract

Recent advances in the study of exchange couplings in magnetic films are introduced. To provide a comprehensive understanding of exchange coupling, we have designed different bilayers, trilayers and multilayers, such as anisotropic hard-/soft-magnetic multilayer films, ferromagnetic/antiferromagnetic/ferromagnetic trilayers, [Pt/Co]/NiFe/NiO heterostructures, Co/NiO and Co/NiO/Fe trilayers on an anodic aluminum oxide (AAO) template. The exchange-coupling interaction between soft-and hard-magnetic phases, interlayer and interfacial exchange couplings and magnetic and magnetotransport properties in these magnetic films have been investigated in detail by adjusting the magnetic anisotropy of ferromagnetic layers and by changing the thickness of the spacer layer, ferromagnetic layer, and antiferromagnetic layer. Some particular physical phenomena have been observed and explained.

Mediating exchange bias by Verwey transition in CoO/Fe3O4 thin film

“…[10][11][12] It has been reported that the EB can be influenced by many factors in FM/ AFM system, such as the FM magnetization M FM , the thickness of FM layer t FM or AFM layer t AFM , and the anisotropy of AFM (K AFM ) or FM (K FM ). [2][3][4]13,14 The exchange bias field (H E ) is inversely proportional to the M FM and t FM , and the K AFM is reported to affect the critical thickness of the AFM layer. 2,3,15,16 Furthermore, the AFM or FM domain formation is also claimed to play a dominant role in EB.…”

“…Therefore, it is found that the H E can be mediated by varying t FM , M FM , or K FM for different FM materials. [2][3][4] To search a FM material that exhibits a big change in K FM leading to a large variation of the H E within the narrow temperature range will be a very interesting issue.…”

Investigation on magnetic properties of parallel and perpendicular oriented Nd2Fe14B/Fe65Co35/Nd2Fe14B films by the micro-magnetism finite element method

“…Major progress of research on nanocomposite magnets in experiment was made in hard/soft multilayers. Zhang et al [6,18,19] added a non-magnetic layer between the soft magnetic layer and hard magnetic layer to enhance the coercivity of in hard/soft multilayers. Large energy product of 486 kJ/m 3 has been achieved in perpendicular anisotropic Nd 2 Fe 14 B/FeCo multilayers by Cui et al [20] in 2012.…”

Learning from Nature: Binary Cooperative Complementary Nanomaterials

“…After the first report of anti‐ferromagnetic coupling in Fe/Cr/Fe trilayer structures, the interlayer exchange coupling in ferromagnetic/non‐magnetic/ferromagnetic multilayer or nanoparticle systems has been widely investigated . Wang et al fabricate a kind of strongly magnetic, zero‐remanence nanoparticles with ferromagnetic multilayer structures (Figure d) .…”