Experimental and theoretical spin configurations in Fe/Gd multilayers

Enhanced exchange and reduced magnetization of Gd in an Fe/Gd/Fe trilayer

“…The magnetization we measure in thin films is 1030 emu/cm 3 , while the bulk value is almost double, 2056 emu/cm 3 . A 20-30% reduction of the magnetization of Gd in Gd/Fe multilayers has previously been reported by several groups, [13][14][15] but very rarely is the reduction as large as the one reported here. 16,17 Beyond the different values obtained for the enhanced exchange and the reduced magnetization of Gd, this work shows that a DSV is an efficient tool for characterizing magnetic materials in general and compounds of REs in particular, which is of great interest for many magnetic research fields.…”

Tunable thermal hysteresis in magnetic multilayers: magnetic superheating and supercooling

“…In addition it is necessary that the magnetization of one material change more rapidly with temperature than the other. An example of such a system is the Fe/Gd multilayer where Gd thermal averaged magnetic moment changes from 7 m B to zero as T changes from 0 to about 300 K. There are a number of known magnetic states for the Fe/Gd system [4][5][6] which are illustrated in Fig. 1.…”

“…If the exchange coupling between films is significant, this may not be a good assumption. We therefore examine the thermal hysteresis in the Fe/Gd system using a selfconsistent local mean-field method that has been used successfully by a number of groups to describe this system [4][5][6][7].…”

Calculations of Bulk-Like Transition Temperatures of Rare Earth-Transition Metal Alloys AcB1-c Using the Effective Field Theory

“…Furthermore, it is not easy to determine how these values are derived even though it seems probable in some cases that a mean-field result is used over a limited interval of concentration in comparison with data for these alloys in their bulk or twodimensional phases in superlattices. The ratios of the magnetic exchange integral values of the model for the RE alloys (Fe-Gd) considered in this study are summarized as follows: 0.03 [21] < J Gd-Gd /J Fe-Fe < 0.15 [22] --1 [22] < J Fe-Gd /J Fe-Fe < --0.5 [21] These values are obtained in each case by comparing a mean-field analysis in a limited range of the concentration with available experimental data in that range, whether for bulk alloy samples or for superlattice samples that contain alloy disordered interfaces on a nanometric scale.…”