Influence of the roughness on the exchange bias effect of NiFe/FeMn/NiFe trilayers

Bottom and top AF/FM interfaces of NiFe/FeMn/NiFe trilayers

“…This result and the other hysteresis loops related to samples e 2 and e 5 have been presented and discussed with more details in ref. [20]. Fig.…”

“…1 displays an asymmetrical loop with two regions related to the seed (region 1) and pinned (region 2) layers. The resulting H ex and H C values are, respectively, (29 AE 1) and (6 AE 1) Oe for the seed layer and (62 AE 1) and (20 AE 1) Oe for the pinned layer [20]. The exchange interfacial energy per unit of area (A FM/AF ) for the bottom and top NiFe/FeMn interfaces was calculated using the expression A FM/AF = J FM/AF / a 2 = H ex t FM M FM from the theoretical model described by Meiklejohn and Bean [3][4][5] for perfect interfaces.…”

“…In previous works [19,20], some of us have shown the dependence of the H ex with the roughness of the lower and upper interfaces (including the atomic grading at the interface) for the NiFe/FeMn/NiFe trilayers prepared at different working pressures. We have also carried out a layer-by-layer investigation on the roughness properties of the interfaces of the Si/WTi/ NiFe/FeMn/WTi multilayer [21], where it was studied how successive layer depositions may change the roughness properties of the subsequent interfaces, and consequently the magnetism of the NiFe/FeMn exchanged-biased system deposited onto the Si/WTi substrate.…”

Influence of surface roughness and deposition order on exchange bias in bilayer structures NiFe/IrMn

“…A major portion of publications shows that exchange bias shift decreases when roughness increases [1][2][3][4], though no significant correlations between H EB and roughness was found in some of the works [5,6]. An opposite effect, that is H EB increasing when roughness increased, was also demonstrated in other investigations, [1,3,7], for instance, in monocrystalline silicone AF (with compensated and uncompensated surface), covered with an F-layer.…”

Ferromagnetic Resonance and X-Ray Reflectivity Studies of Pulsed DC Magnetron Sputtered NiFe/IrMn/CoFe Exchange Bias

“…However, due to the wide variety of materials and deposition techniques used, the dependence of the EB field (H ex ) on the roughness is still controversial. For several systems, the H ex seems to be relatively insensitive to the roughness value [7,11], while in others the H ex varies in direct proportion to the roughness [9,10] or indicates an opposite variation [8]. Research has also shown that the relationship between the H ex and the roughness value is totally different for differently prepared samples [12].…”