Related papers: High-output CPP-GMR sensor with synthetic-ferrimag…
It is experimentally shown that the critical current for onset of spin-torque instability in current-perpendicular-to-plane spin-valves can be strongly enhanced using "synthetic ferrimagnet" free-layers of form FM1/Ru/FM2 (FM=ferrromagnet).…
This paper derives expressions for the critical current at the onset of spin-transfer-torque (STT) instability in CPP-GMR read heads, as a function of the relative angle (theta) between the free and reference layer magnetizations. Including…
Emerging spin-orbit-torque devices based on spin valves require a thin magnetic free layer to maximize the torque per moment. However, reducing the free-layer thickness to $\lesssim 2$ nm deteriorates the giant magnetoresistance (GMR)…
We have developed a self-aligned, high-yield process to fabricate CPP (current perpendicular to the plane) magnetic sensors of sub 100 nm dimensions. A pinned synthetic antiferromagnet (SAF) is used as the reference layer which minimizes…
Magnetoresistive spin valve sensors based on the giant- (GMR) and tunnelling- (TMR) magnetoresisitve effect with a flux-closed vortex state free layer design are compared by means of sensitivity and low frequency noise. The vortex state…
Critical current density of composite free layer (CFL) in magnetic tunneling junction is investigated. CFL consists of two exchange coupled ferromagnetic layers, where the coupling is parallel or anti-parallel. Instability condition of the…
In-situ, device level measurement of thermal mag-noise spectral linewidths in 60nm diameter CPP-GMR spin-valve stacks of IrMn/ref/Cu/free, with reference and free layer of similar CoFe/CoFeGe alloy, are used to simultaneously determine the…
Spin-torque driven ferromagnetic resonance (ST-FMR) is used to study thin Co/Ni synthetic layers with perpendicular anisotropy confined in spin-valve based nanojunctions. Field swept ST-FMR measurements were conducted with a magnetic field…
Current-induced dynamics in spin valves including composite free layer with antiferromagnetic interlayer exchange coupling is studied theoretically within the diffusive transport regime. We show that current-induced dynamics of a synthetic…
We develop a high-throughput method for measuring the composition dependence of magnetoresistance (MR) and spin-transfer-torque (STT) effects in current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) devices and report its…
In contrast to earlier studies performed on simple Co/Cu/Co sandwiches, we have investigated spin transfer effects in complex spin-valve pillars with a diameter of 130nm developed for current-perpendicular to the plane (CPP)…
Measurements of Giant Magnetoresistance (GMR) in ferromagnetic/non-magnetic (F/N) multilayers with Current flow Perpendicular to the layer Planes (CPP-geometry) can give better access to the fundamental physics underlying GMR than…
We demonstrate a strong tunability of the spin-pumping contribution to magnetic damping in a thin-film ferromagnetic free layer interfaced with a synthetic ferrimagnet (SFM), acting as a spin-sink, via a thin Cu-spacer. The effect strongly…
Spin transfer in asymmetric Co/Cu/Co bilayer magnetic nanopillars junctions has been studied at low temperature as a function of free-layer thickness. The phase diagram for current-induced magnetic excitations has been determined for…
Spin-transfer torque (STT) in magnetoresistance devices has enabled key applications such as STT-magnetoresistive random access memory, spin torque oscillators, and energy-assisted magnetic recording. In the device structures, where a free…
The non-linear parameters of spin-torque oscillators based on a synthetic ferrimagnet free layer (two coupled layers) are computed. The analytical expressions are compared to macrospin simulations in the case of a synthetic ferrimagnet…
We present a comprehensive review of data and analysis of Giant (G) Magnetoresistance (MR) with Current-flow Perpendicular-to-layer-Planes (CPP-MR) of magnetic multilayers [F/N]n (n = number of repeats) with alternating nanoscale layers of…
We develop a macroscopic description of the current-induced torque due to spin transfer in a layered system consisting of two ferromagnetic layers separated by a nonmagnetic layer. The description is based on i) the classical spin diffusion…
We investigated the effect of using a synthetic ferrimagnetic (SyF) free layer in MgO-based magnetic tunnel junctions (MTJs) on current-induced magnetization switching (CIMS), particularly for application to spin-transfer torque random…
The switching speed and the write current required for spin-transfer-torque reversal of spintronic devices such as magnetic tunnel junctions (MTJ) currently hinder their wide implementation into memory and logic devices. This problem is…