Electrode Design for Antiparallel Magnetization Alignment in Nanogap Devices

Abstract

The ability to manipulate the relative magnetization alignment between ferromagnetic source and drain electrodes attached to a molecule or small quantum dot is a prerequisite for a number of spintronic device applications. The influence of electrode shape and field orientation on pair-wise magnetization reversal mechanisms in nanogap and point-contact structures is investigated here using micromagnetic simulations. A favorable device geometry and setup are identified for enabling planar, monodomain source and drain electrodes with a magnetization alignment that may be controllably switched between a parallel and anti-parallel configuration.

Controlled electrode magnetization alignment in planar elliptical ferromagnetic break junction devices

“…The unbroken version contains a bridge of finite width (8 − 12nm) between the electrodes; the point-contact has a bridge constricting down to a single point; the nanogap includes a tapered bridge possessing a roughly 2nm gap; and the ideal set of leads consists of the ellipses without the constriction. [11] RESULTS AND DISCUSSION Longitudinal Configuration…”

“…Each sample con-sists of a pair of closely-spaced planar ellipses connected by a narrow constriction. [11] The nanoscale contacts are formed by reducing the size of a constriction using an electromigration technique. The reversal process is analyzed via MR measurements, which are shown to be consistent with numerical simulations.…”