Asymmetric domain wall propagation in a giant magnetoresistance-type wire with oscillating interlayer exchange coupling

Abstract

Quantum interference incorporating spatially asymmetric potential profiles is realized experimentally to manipulate a magnetic domain wall (DW) into a single giant magnetoresistance (GMR)-type wire whose spacer has a thickness gradient for generating asymmetrical interlayer exchange coupling from side to side. We demonstrate experimentally how to guide a DW in a microscale ferromagnetic wire without reflection symmetry of the interlayer exchange coupling. This is the first observation of asymmetric DW propagation in the wire with oscillating interlayer exchange coupling. The experimental results can be described well by numerical simulations considering spatially asymmetric potential profiles due to quantum interference. © 2010 The Japan Society of Applied Physics.