Large Magnetoresistance at Room Temperature in Ferromagnetic Thin Film Tunnel Junctions

This is the authors' abstract. We don't add key points for this paper.

Ferromagnetic-insulator-ferromagnetic tunneling has been measured in CoFe $/$Al₂{O}₃$ $/$Co or NiFe junctions. At 295, 77, and 4.2 K the fractional change in junction resistance with magnetic field, ${Δ}R/R$, is 11.8%, 20%, and 24%, respectively. The value at 4.2 K is consistent with Julliere's model based on the spin polarization of the conduction electrons of the magnetic films. ${Δ}R/R$ changes little with a small voltage bias, whereas it decreases significantly at higher bias $(>0.1V)$, in qualitative agreement with Slonczewski's model. These junctions have potential use as low-power field sensors and memory elements.