Crossbar-Compatible Stateful Logic Using Phase Change Memory

Stateful logic is a digital processing-in-memory technique that could address von Neumann memory bottleneck challenges while maintaining backward compatibility with von Neumann architectures. In stateful logic, memory cells are used to perform the logic operations without reading or moving any data outside the memory array. This has been previously demonstrated using several resistive memory types, but not with commercially available phase-change memory (PCM). Here we present the first implementation of stateful logic using PCM. We experimentally demonstrate four logic gate types (NOR, IMPLY, OR, NIMP) using commonly used PCM materials and crossbar-compatible structures. Our stateful logic gates form a functionally complete set, which enables sequential execution of any logic function within the memory and paves the way to PCM-based digital processing-in-memory systems.