Geometric symmetry breaking of current distribution enables field-free programmable spin logic in T-shaped architecture

Abstract

Achieving fully electrical and easily integrated programmable spin logic within a single device using spin–orbit torque (SOT)-driven perpendicular magnetization switching (PMS) remains a key challenge for realizing scalable and energy-efficient spin logic-in-memory computing. Here, we demonstrate controllable field-free SOT-driven PMS by the geometric asymmetry of current distribution in a “T-shaped” Pt/CoPt architecture. Deterministic clockwise/counterclockwise PMS is observed when applying current pulses along the left/right arms of the T-architecture, which has been attributed to the combined effect of geometrically curved current channel-induced Oersted field and inhomogeneous spatial distribution of spin currents. Furthermore, by implementing a three-step sequential pulsing scheme that precisely controls channel selection, an initial control current pulse, and two subsequent control pulses, we demonstrate the complete set of 16 Boolean logic functions within a single device. This simple material-agnostic and integration-friendly approach provides a pathway for developing fully electrical controllable SOT-based spin logic and in-memory computing devices.