MgO Tunneling Spintronics across Capacitively Coupled Atomic Clusters.

Abstract

Transport across model junctions built by using atomic tip or lateral techniques can generate exotic quantum signatures. However, so far, a viable industrial pathway for atom-driven electronics has been lacking. Here, we demonstrate that a commercialized device platform can help to fill this nanotechnological gap. According to conducting tip atomic force microscopy, inserting C atoms into an ultrathin MgO layer generates nanotransport paths. Across microscale magnetic tunnel junctions, resonant tunneling causes large magnetoresistance peaks that we attribute to spin accumulation onto a C nanodot that the channels transport. We ascribe the concurrent presence of a spectrally localized, nonlinear current noise and a persistent memory effect to the charging of a 'gating' C nanodot, adjacent to the 'transport' C nanodot. This nanoscale dual-dot description of quantum transport across spin states within a microscale magnetic tunnel junction should stimulate further research toward maturing spintronics into a viable quantum technological track.