Current-field diagram for the magnetic states of a surface spin valve in a point contact with a single ferromagnetic film

Abstract

Articles you may be interested inSpin-valve effects in point contacts to exchange biased Co40Fe40B20 films Low Temp. Phys. 40, 915 (2014); 10.1063/1.4897413 Field and current-induced magnetization reversal studied through spatially resolved point-contactsThis is a study of the influence of an external magnetic field H and an electric current I on the spin-valve (SV) effect in a point contact between a ferromagnetic thin film (F) and a sharp, nonmagnetic metal tip (N). To explain our observations, we propose a model for a local surface SV in an N/F contact of this type. In this model, a ferromagnetic cluster at the N/F interface serves as the free layer in the SV. This cluster has a larger coercive field than the bulk of the ferromagnetic film, presumably due to its nanoscale nature. Finally, we construct a magnetic state diagram of the surface SV as a function of I and H. V C 2013 American Institute of Physics.

Ferromagnetic resonance in copper-permalloy point contacts

“…5(a) reversal of the film bulk (at low fields) and of single-domain surface magnetic clusters in high fields. 10 This type of behavior is typical of point contacts with a surface spin valve. [9][10][11] These kinds of contacts could also have hysteresis in the resistance as a function of a constant bias dV/dI(V), if the cluster size is sufficiently small that the spin torque of the transport current electron flux could significantly act on the magnetic moment of a cluster, thereby changing the direction of its magnetization vector.…”

“…9,10 Surface spin valves of this type have all the static and dynamic magnetic properties characteristic of traditional F 1 -N-F 2 structures. [9][10][11] It is well known 4 that, because of the giant magnetoresistance effect, 12 the electrical resistance of a spin valve depends on the mutual orientation angle of the magnetic moments of the ferromagnetic films that form this kind of structure (Figs. 1(a) and 1(c)).…”

Spin-valve effects in point contacts to exchange biased Co40Fe40B20 films

“…In our previous papers [10][11][12][13] it was shown that in nonmagnetic-ferromagnetic singleinterface tip-surface point contacts, with the ferromagnet being polycrystalline Co, the magnetotransport exhibits many of the characteristic of traditional pillar-like F 1 /N/F 2 spin-valves (with two magnetic interfaces, having parallel and antiparallel spin configuration). Our analysis of the experiments resulted in a spin-transport model for a single F/N interface in the point contact region [11,13]. The model proposes that an atomically thin surface layer of spins in cobalt is magnetically rotated with respect to the spins in the bulk, forming an atomically thin domain wall.…”