Complementary Lateral-Spin-Orbit Building Blocks for Programmable Logic and In-Memory Computing

Current-driven switching of nonvolatile spintronic materials and devices based on spin-orbit torques offer fast data processing speed, low power consumption, and unlimited endurance for future information processing applications. Analogous to conventional complementary metal-oxide-semiconductors technology, it is important to develop complementary spin-orbit devices with differentiated magnetization switching senses as elementary building blocks for realizing sophisticated logic functionalities. Various attempts using external magnetic field or complicated stack/circuit designs have been proposed; however, plainer and more feasible approaches are still strongly desired. Here it is shown that a pair of two locally laser annealed perpendicular Pt/Co/Pt devices with opposite laser track configurations and thereby inverse field-free lateral spin-orbit torques (LSOTs) induced switching senses can be adopted as such complementary spin-orbit building blocks. By electrically programming the initial magnetization states (spin down/up) of each sample, Boolean logic gates of AND, OR, NAND, and NOR as well as a spin-orbit half adder containing an exclusive-OR gate are obtained. Moreover, various initialization-free programmable stateful logic operations, including material implication gate, are also demonstrated by regarding the magnetization state as a logic input. The complementary LSOT building blocks provide a potentially applicable way toward future efficient spin logics and in-memory computing architectures.