An interface study of crystalline Fe/Ge multilayers grown by molecular beam epitaxy

Abstract

a b s t r a c tFe/Ge multilayers were grown on single crystal Ge(0 0 1) substrates by molecular beam epitaxy. The structural, electronic and magnetic properties of Fe/Ge have been studied. The analysis shows that Fe grows in a layer-by-layer epitaxial growth mode on Ge(0 0 1) substrates at 150 • C and no intermixing has been observed. Growth of a crystalline Ge film at 150 • C on a single crystal Fe film has been observed. At this temperature Ge films grow by means of the island growth mode according to reflection of high energy electron diffraction patterns. Fe layers of 36 nm thickness, deposited at 150 • C on Ge(0 0 1) substrates, show two magnetization reversal values indicating the growth of Fe in two different crystal orientations. 36 nm thick Fe and Ge layers grown at 150 • C in Ge/Fe/Ge/Fe/Ge(0 0 1) sequence shows ferromagnetic behavior, however, the same structure grown at 200 • C shows paramagnetic behavior.

The influence of ultrathin Cu interlayer in NiFe/IrMn interface on rotation of the magnetic moments

“…So the interfacial roughness will be decreased and the upper interface on NiFe layer will be smoother. Although the exchange bias coupling will be weaker after the Cu insertion, the decreased exchange bias field with smoother interface not only provides the pinning direction for magnetic moments, but also can make the magnetic moments rotate more consistently with the decreased rotation frustration [11,[21][22][23].…”

Room Temperature Ferromagnetic, Anisotropic, Germanium Rich FeGe(001) Alloys

“…We must stress here that this is the first time that ferromagnetism is detected in a Ge-rich Fe–Ge surface compound. Also, along the [110] in-plane direction the ferromagnetism is quite robust, since the coercitive field is about 230 Oe, much larger than the reported coercitive fields for Fe grown on Ge [16,17,18,19,20,21]. The measured coercitive fields for FeGe(001) largely exceed that of metal Fe or even of reacted Fe on Si(001) [10,11].…”

“…Comparatively, there are fewer efforts to work on Fe–Ge systems, although iron is a better magnet than manganese. Efforts are continuously concentrated in the synthesis of well ordered and low intermixing Fe layers on Ge(001) [ 4 , 16 , 17 , 18 , 19 , 20 , 21 ], (011) [ 22 ] or (111) surfaces [ 23 , 24 ]. Basically, most Fe layers are reported to be ferromagnetic with an onset of ferromagnetism at few (3–5) atomic iron layers [ 19 , 23 ].…”

“…Basically, most Fe layers are reported to be ferromagnetic with an onset of ferromagnetism at few (3–5) atomic iron layers [ 19 , 23 ]. One phenomenon reported in most of these studies is the occurrence of uniaxial magnetic anisotropy [ 16 , 17 , 18 , 19 , 20 , 21 ] with the in-plane [110] easy axis for thin Fe films, changing to in-plane easy axis [100] for thicker films [ 18 , 19 ]. The in-plane easy axis [110] can be very well connected to the well known in plane uniaxial magnetic anisotropy of Fe/GaAs(001) [ 1 ], whereas the other easy axis is connected to the formation of bulk bcc Fe and eventually to ripples formed on the surface during the growth of the Fe film [ 18 ].…”

Heterostructures design for Hf-Nitride/V-Nitride system

“…Tuning the size distribution and spatial ordering of these structures remains a continuing challenge. Metal/metal, metal/ceramic and ceramic/ceramic are type of the model materials used in the investigation of the selforganization of nanostructures in semiconductor and mechanical heterostructures [3][4][5]. In the case of iso-structural multilayers (e.g., NaClfcc-NaClfcc), molecular dynamics (MD) simulations have shown that the peak strength is set by coherency stresses which in turn are determined by elastic modulus and lattice parameter mismatch [6].…”