A ferromagnetic skyrmion-based diode with a voltage-controlled potential barrier

Traditional electronic technologies face many challenges, such as the scalability of equipment and improvement of performance. Some novel spintronic objects are expected to improve electronic applications for the more-than-Moore era. For example, a magnetic skyrmion is a potential building block for the next generation of electronic devices due to its small size, good stability and low driving current threshold. However, the Magnus force acting on a ferromagnetic skyrmion can induce a transverse motion perpendicular to the driving force, which may lead to the destruction of skyrmions at sample edges. Here, we computationally demonstrate that the nanotrack edge with high magnetic perpendicular anisotropy (PMA), which is controlled by the voltage-controlled magnetic anisotropy (VCMA) effect, not only enables the reliable motion of skyrmions along the nanotrack, but also increases the skyrmion velocity. The one-way motion of skyrmions can be realized by applying voltage to create high PMA at a local area near the nanotrack edge. In addition, we show a feasible design of a skyrmion diode similar to the P-N junction. Our results may provide guidelines for designing skyrmion-based diodes.