Magnetic racetrack with current-controlled motion of domain walls within an undulating energy landscape

Abstract

A racetrack memory device facilitates the manipulation of a series of domain walls along the racetrack. The racetrack is designed so that the domain wall energy increases and decreases in a continuous fashion between adjacent pinning sites, so that a domain wall does not become stuck between them. The variation in the domain wall energy along the racetrack can be provided by continuous variations of the racetrack's width (while maintaining constant thickness) and/or cross-sectional area (in which the racetrack dimensions are varied in both directions perpendicular to the length of the racetrack). Alternatively, this variation in domain wall energy may be provided by varying the magnetic properties of the racetrack along the racetrack while otherwise keeping the shape and size of the racetrack unchanged. In addition, variations of the racetrack's composition and/or shape can be used.

Dependencies are inferred from the claim text.