title: Spatially modulated tunnel magnetoresistance on the nanoscale.
abstract: We investigate the local tunnel magnetoresistance (TMR) effect within a single Co nanoisland using spin-polarized scanning tunneling microscopy. We observe a clear spatial modulation of the TMR ratio with an amplitude of ~20% and a spacing of ~1.3 nm between maxima and minima around the Fermi level. This result can be ascribed to a spatially modulated spin polarization within the Co island due to spin-dependent quantum interference. Our combined experimental and theoretical study reveals that spin-dependent electron confinement affects all transport properties such as differential conductance, conductance, and TMR. We demonstrate that the TMR within a nanostructured magnetic tunnel junction can be controlled on a length scale of 1 nm through spin-dependent quantum interference.
authors: Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle/Saale, Germany.
authors: Hirofumi
authors: H
authors: Oka
authors: Kun
authors: K
authors: Tao
authors: Sebastian
authors: S
authors: Wedekind
authors: Guillemin
authors: G
authors: Rodary
authors: Valeri S
authors: VS
authors: Stepanyuk
authors: Dirk
authors: D
authors: Sander
authors: Jürgen
authors: J
authors: Kirschner