Current-Controlled Skyrmionic Diode
  In order to address many of the challenges and bottlenecks currently experienced by traditional charge based technologies, various alternatives are being actively explored to provide potential solutions of device miniaturization and scaling in the more-than-MOORE era. Amongst these alternatives, spintronics physics and devices have recently attracted a rapidly increasing interest by exploiting the additional degree of electron's spins. For example, magnetic domain-wall racetrack-memory and logic devices have been realized via manipulating domain-wall motion. As compared to domain-wall based devices, magnetic skyrmions have the advantages of ultra-small size (typically 5-100 nm in diameter), facile current-driven motion, topological stability and peculiar emergent electrodynamics, promising for next-generation electronics applications in the more-than-Moore regime. In this work, a magnetic meron diode, which behaves like a PN-junction diode, is demonstrated for the first time, by tailoring the current-controlled unidirectional motion of edge-merons (i.e., fractional skyrmions) in a nanotrack with interfacial Dzyaloshinskii-Moriya interaction. The working principles of the meron diode, theoretically expected from the Thiele equation for topological magnetic objects, are further verified by micromagnetic simulations. The present study reveals topology-independent transport property of magnetic objects, and is expected to open the vista toward integrated composite circuitry, with unified data storage and processing, based on a single magnetic chip, as the meron diode can be used either, as a building block, to develop complex logic components or, as a signal controller, to interconnect skyrmion, domain-wall, and even spin-wave devices. 
Xiangjun Xing, Philip W. T. Pong, and Yan Zhou
cond-mat.mes-hall cond-mat.mtrl-sci