Properties of the roughness in NiFe/FeMn exchange-biased system

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

“…The method used to fit realistic results in function of the initial values was described in details in ref. [21]. The thickness values are similar to those nominal ones.…”

“…For this purpose, the layers were sequentially deposited and measured by X-ray reflectivity, using the same method described with details in ref. [21]. Thus, each series is formed by five samples which were nominated by the letters: a for (Si/WTi), b for (Si/WTi/NiFe), c for (Si/WTi/NiFe/ FeMn), d for (Si/WTi/NiFe/FeMn/NiFe) and e for (Si/WTi/ NiFe/FeMn//NiFe/WTi).…”

“…It was also proposed a possible explanation for the discrepancy found in the literature [24][25][26][27][28] about the dependence of the EB effect on the rootmean-square roughness (s). This purpose was based on the Malozemoff model for the EB effect [22,23], considering other roughness properties, like the correlation length (j) and the fractal dimension (D) parameters [21]. Now we extended the work by studying the effect of the pinned NiFe layer deposition on the Si/WTi/NiFe/FeMn/ multilayer by using X-ray reflectivity measurements.…”

“…Specifically, the s value of the upper FeMn/NiFe interface (including the atomic grading at the interface) after the pinned NiFe layer deposition has been quantitatively obtained and compared to that related to the seed NiFe layer. Following the systematic of our previous work [21] we also investigated: (i) the influence of this deposition over the roughness cumulative process [29] on the subsequent interfaces; (ii) the influence of the argon working pressure on the structural characteristics of each interface of the multilayer and (iii) why lower and upper FeMn/ NiFe interfaces have substantial differences. For this purpose, layer-by-layer analyses were done in similar samples prepared with different working pressures, to prove that the observed effect is valid for different s ranges.…”

“…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. It was also proposed a possible explanation for the discrepancy found in the literature [24][25][26][27][28] about the dependence of the EB effect on the rootmean-square roughness (s).…”