Giant magetoresistance in epitaxial sputtered Fe/Cr(211) superlattices (abstract)

We report giant magnetoresistance (GMR) as high as 150% at 4.2 K in epitaxial Fe/Cr superlattices. Samples prepared by magnetron sputtering on MgO(100) produced the expected Fe/Cr(100) orientation; however, deposition on MgO(110) produced a novel (211) low‐miller‐index orientation. The crystallographic orientations and superlattice nature of the samples were confirmed by both low‐ and high‐angle x‐ray diffraction. The Fe/Cr(211) superlattices have an in‐plane uniaxial anisotropy (KU=9×105 ergs/cm3) along the Fe[011] which give the sample a rich magnetic behavior. The GMR with the current along the [011] is ≊20% higher than that along the [111] direction of the (211) plane. The GMR for the (211) superlattices shows four oscillations with Cr thickness. Both orientations shows the expected long‐period oscillation of 18 A Cr and a GMR increase by a factor a 4 when cooled from room temperature to 4.2 K.