Exchange anisotropy of MBE grown Mn1−Pt /NiFe bilayers with (0 0 1) orientation

Exchange anisotropy of (001)-oriented Mn80Ir20/NiFe epitaxial bilayers

“…Sample construction of (0 0 1) oriented Mn 80 Ir 20 /NiFe bilayers.depends on the crystal orientation of Mn 89 Pt 11 , rather than on the direction of the magnetic field during the growth. However, the previous Mn 89 Pt11 /NiFe showed double shifted M2H loops when the magnetic field was applied along hard directions ½11 0 and ½1 1 0[9,10]. The double shifted loops are not observed in the present Mn 80 Ir 20 /NiFe bilayers as seen fromFig.…”

“…For (0 0 1)-oriented Mn 89 Pt 11 /NiFe epitaxial bilayers, a large H ex was obtained without heat treatment [9]. The easy direction of the unidirectional anisotropy was parallel to /1 1 0S direction regardless of the field direction applied during the deposition [10]. Furthermore, the Mn 89 Pt 11 /NiFe bilayers showed a quite large 4-fold magnetic anisotropy [10].…”

“…Most of the studies on Mn 50 Pt 50 /ferromagnet and Mn 80 Ir 20 /ferromagnet bilayers have been done with sputtered films but very few have been performed with molecular-beam-epitaxy (MBE) grown bilayers. Thus, we have investigated the [9,10] and (1 1 1) [11] at the substrate temperature T g =room temperature. For (0 0 1)-oriented Mn 89 Pt 11 /NiFe epitaxial bilayers, a large H ex was obtained without heat treatment [9].…”

Thickness dependence of exchange anisotropy for (0 0 1) oriented Mn89Pt11/NiFe and Mn80Ir20/NiFe bilayers

“…We have studied the exchange anisotropies of (0 0 1) oriented Mn 100Àx Pt x /NiFe epitaxial bilayers around x ¼ 10 at%, since Mn 90 Pt 10 /NiFe is known to exhibit a large exchange biasing field without heat treatment [6], and epitaxial bilayers are useful to insight the relationship between the exchange anisotropy and the crystalline anisotropy of the AF layer. The (0 0 1) oriented Mn 90 Pt 10 /NiFe exhibited both strong 1-and 4-fold anisotropies in their in-plane torque curves [7]. The large 4-fold anisotropy is considered to result from the cubic anisotropy of AF Mn 100Àx Pt x .…”

Temperature dependence of exchange anisotropy for (0 0 1) oriented Mn89Pt11/ferromagnetic bilayers

“…We have studied the exchange anisotropies of (0 0 1) oriented Mn 100Àx Pt x /NiFe epitaxial bilayers around x ¼ 10 at%, since Mn 90 Pt 10 /NiFe is known to exhibit a large exchange biasing field without heat treatment [6], and epitaxial bilayers are useful to discuss the relationship between the exchange anisotropy and the crystalline anisotropy of the AF layer. The (0 0 1) oriented Mn 90 Pt 10 /NiFe exhibited both 1 and 4-fold anisotropies in their in-plane torque curves [7]. The large 4-fold anisotropy, which results in the large coercivity, is considered to result from the cubic anisotropy of AF Mn 100Àx Pt x , since the uncoupled NiFe has negligibly small 4-fold anisotropy.…”