Large inverse tunneling magnetoresistance in Co${}_2$Cr${}_{0.6}$Fe${}_{0.4}$Al/MgO/CoFe magnetic tunnel junctions

Abstract

Magnetic tunnel junctions with the layer sequence Co${}_2$Cr${}_{0.6}$Fe${}_{0.4}$Al/MgO/CoFe were fabricated by magnetron sputtering at room temperature (RT). The samples exhibit a large inverse tunneling magnetoresistance (TMR) effect of up to -66% at RT. The largest value of -84% at 20 K reflects a rather weak influence of temperature. The dependence on the voltage drop shows an unusual behavior with two almost symmetric peaks at $\pm 600$ mV with large inverse TMR ratios and small positive values around zero bias.

References in corpus (4)

• Large magnetoresistance in bcc Co/MgO/Co and FeCo/MgO/FeCo tunneling junctions
• Appearance of Half-Metallicity in the Quaternary Heusler Alloys
• Inverted spin polarization of Heusler alloys for new spintronic devices
• Structural and magneto-transport characterization of Co_2Cr_xFe_(1-x)Al Heusler alloy films