Beyond von-Neumann computing with nanoscale phase-change memory devices
Advanced Functional Materials
Historically, the application of phase-change materials and devices has been limited to the provision of non-volatile memories. Recently however the potential has been demonstrated for using phase-change devices as the basis for new forms of brain-like computing, by exploiting their multi-level resistance capability to provide electronic mimics of biological synapses. Here we exploit a different and previously under-explored property also intrinsic to phase-change materials and devices, namely accumulation, to demonstrate that nanoscale electronic phase-change devices can also provide a powerful form of arithmetic computing. We carry out complicated arithmetic operations, including parallel factorization and fractional division, using simple nanoscale phase-change cells that process and store data simultaneously and at the same physical location, promising a most efficient and effective means for implementing 'beyond von-Neumann' computing. We also show that this same accumulation property can be used to provide a particularly simple form phase-change integrate-and-fire 'neuron' which, by combining both phase-change synapse and neuron electronic mimics, potentially opens up a route to the realization of all-phase-change neuromorphic processing.
The authors gratefully acknowledge EPSRC for grant funding (EP/ F015046/1). They also would like to thank Dr. A Pauza, formerly of Plasmon Data Systems Ltd, for help in preparation of the GST samples. Professor Peter Ashwin from the University of Exeter is also acknowledged for helpful discussions and guidance in the formulation of the GCA simulator. The authors are also very grateful to Mr. David Anderson of the University of Exeter for valuable assistance with the lithography of the pseudo-devices.
This is the final version of the article. Available from the publisher via the DOI in this record.
Vol. 23, pp. 2248 - 2254