Control of the noncollinear interlayer exchange coupling

Abstract

Interlayer exchange coupling in transition metal multilayers has been intensively studied for more than three decades and is incorporated into almost all spintronic devices. With the current spacer layers, only collinear magnetic alignment can be reliably achieved; however, controlling the coupling angle has the potential to markedly expand the use of interlayer exchange coupling. Here, we show that the coupling angle between the magnetic moments of two ferromagnetic layers can be precisely controlled by inserting a specially designed magnetic metallic spacer layer between them. The coupling angle is controlled solely by the composition of the spacer layer. Moreover, the biquadratic coupling strength, responsible for noncollinear alignment, is larger than that of current materials. These properties allow for the fabrication and study of not yet realized magnetic structures that have the potential to improve existing spintronic devices.

Impact of GO on Non-stoichiometric Mg0.85 K0.3Fe2O4 Ferrite Nanoparticles

“…(3) SFD = ΔH Hc interactions [36][37][38]. In the case study, the dipolar interactions are more effective, for the testified samples, which implies a strong reduction of the inter bump exchange coupling in our bump array.…”

Effect of interlayer exchange coupling in spin-torque nano oscillator

“…In an STNO the tunability in the thickness of the 3d, 4d and 5d nonmagnetic metallic spacer layer leads to ferromagnetic or antiferromagnetic coupling between the free and pinned ferromagnetic layers. This inter-layer exchange coupling has been intensively investigated since 1980s [15][16][17][18][19]21 . Recent results in this context show that the presence of exchange coupling in a magnetic layer structure is mostly applicable to modern STT magnetic random-access memory (MRAM) and sensor devices [17][18][19] .…”

“…Very recently, Nunn et al 21 have reported that a noncollinear alignment between the magnetizations of the free and pinned layers can be achieved and precisely controlled when they are coupled across a spacer layer consisting a non-magnetic material (Ru) alloyed with a ferromagnetic material (Fe). This noncollinear aligna) Electronic mail: chandru25nld@gmail.com ment happens due to the biquadratic coupling which can be tuned by changing the composition and thickness of the spacer layer 21 . This Co |RuFe| Co structure is useful for the noncollinear spintronic design with magnetic moments tilted to the film plane [17][18][19]21 .…”

“…This noncollinear aligna) Electronic mail: chandru25nld@gmail.com ment happens due to the biquadratic coupling which can be tuned by changing the composition and thickness of the spacer layer 21 . This Co |RuFe| Co structure is useful for the noncollinear spintronic design with magnetic moments tilted to the film plane [17][18][19]21 . Nevertheless, there is a lack of understanding about the impact of noncollinear alignment on the dynamics of the magnetization of the free layer in an STNO which is yet to be understood.…”

Skyrmion bound state and dynamics in an antiferromagnetic bilayer racetrack

“…In this context, we consider that exchange-like interactions can mediate the coupling between the layers [40,41], where its strength decays exponentially with separation between the layers (or the thickness of the spacer) [42]. Several experimental works [13,[43][44][45][46][47][48][49][50][51] showed the possibility to manipulate the interlayer interaction artificially, where the ferro-or antiferromagnetic coupling is selected by inserting a magnetic metallic spacer with a controlled chemical composition. Our results evidence that depending on the distance between the skyrmions a bound-state of them is achieved.…”