The dynamics of current-driven skyrmions are crucial for applications in spintronics and data storage. However, inevitable random defects in materials introduce uncontrollable factors affecting skyrmion mobility. In this study, we investigate the critical dynamics of current-driven skyrmions under a voltage-controlled Rashba effect in the two-dimensional ferromagnet with quenched disorder. Using the nonstationary dynamic approach, we accurately determine critical currents and exponents for various Rashba parameters. The theoretical analysis establishes an upper limit for the critical current, which depends solely on the disorder strength and the skyrmion topological number and agrees well with numerical simulations. Notably, when the Rashba parameter is large, a directional locking phenomenon emerges, where skyrmions exhibit absolute transverse motion within a specific driving range above the critical current. Furthermore, leveraging the phase transition mechanisms, we design an all-electrically controlled multiport skyrmion-based device and a skyrmionic synapse. Our results demonstrate an efficient method to control skyrmions in disordered materials via phase transitions, emphasizing the potential of skyrmions in computing and storage devices.

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• Dynamical phase transitions
• Hall effect
• Skyrmions
• Spin transfer torque
• Spin-orbit torque