Ab Initio Molecular-Dynamics Simulation of Neuromorphic Computing in Phase-Change Memory Materials

Jonathan M Skelton; Desmond Loke; Taehoon Lee; Stephen R Elliott

doi:10.1021/acsami.5b01825

Ab Initio Molecular-Dynamics Simulation of Neuromorphic Computing in Phase-Change Memory Materials

ACS Appl Mater Interfaces. 2015 Jul 8;7(26):14223-30. doi: 10.1021/acsami.5b01825. Epub 2015 Jun 23.

Authors

Jonathan M Skelton¹, Desmond Loke^{1

2}, Taehoon Lee¹, Stephen R Elliott¹

Affiliations

¹ †Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
² ‡Department of Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore 487372, Singapore.

PMID: 26040531
DOI: 10.1021/acsami.5b01825

Abstract

We present an in silico study of the neuromorphic-computing behavior of the prototypical phase-change material, Ge2Sb2Te5, using ab initio molecular-dynamics simulations. Stepwise changes in structural order in response to temperature pulses of varying length and duration are observed, and a good reproduction of the spike-timing-dependent plasticity observed in nanoelectronic synapses is demonstrated. Short above-melting pulses lead to instantaneous loss of structural and chemical order, followed by delayed partial recovery upon structural relaxation. We also investigate the link between structural order and electrical and optical properties. These results pave the way toward a first-principles understanding of phase-change physics beyond binary switching.

Keywords: ab initio molecular-dynamics simulations; brain-inspired/neuromorphic computing; computational modeling; electronic synapse; phase-change materials.

Publication types

Research Support, Non-U.S. Gov't