Output enhancement of spin-valve giant magnetoresistance in current-perpendicular-to-plane geometry

Abstract

In this work, we present a suitable material for metal-based spin-valve in current-perpendicular-to-plane (CPP) geometry. The AΔR (A is the element size and ΔR is the change in resistance) was investigated for three kinds of free and pinned layers material, that is, Co90Fe10, Fe50Co50, and Fe50Co50 with half-atomic Cu layers. When the free and pinned layers are 5 nm, AΔR is 1.0 mΩ μm2, 1.6 mΩ μm2, and 2.9 mΩ μm2, respectively. Moreover, the dual-type spin valve having Fe50Co50 with half-atomic Cu layers achieved 5.2 mΩ μm2. According to the free and pinned layers thickness dependence of AΔR, the spin-dependent resistance at the interfaces between ferromagnetic layers and spacer Cu is enhanced mainly by changing from Co90Fe10 to Fe50Co50, and the spin-dependent bulk resistance in free and pinned layers is enlarged by inserting half-atomic Cu layers.

Magnetic recording read head sensor technology

“…Consequently, the optimization of GMR is an important challenge for future CPP sensors. It has already been demonstrated that appropriate laminations in the magnetic layers can significantly increase RA [32]. However, further improvements are still required to increase the effective signal in CPP-GMR sensors.…”

CPP-GMR: Materials and Properties

“…100 mm and r 10 mm, R c will be comparable to R s . Since this R c is the same for AR AP and AR P , it will not affect ADR, but will reduce the CPP-MR. Because the "ln" term varies weakly with (1/r) / (1/ ffiffiffi A p ), for a small enough range of 1/A, a plot of the measured AR m versus 1/A might approximate a straight line with slope AR P or AR AP [109]. 2.…”

Magnetoresistance modulation due to interfacial conductance of current perpendicular-to-plane spin valves

“…In recent years the CPP mode of conduction is increasingly preferred in spin valves as it can potentially achieve a higher GMR ratio [4][5][6][7][8][9]. The GMR ratio is defined as the fractional change in resistance when the magnetization alignment in the spin-valve multilayer switches from a parallel to an antiparallel alignment.…”