(Invited) Ion Tunable Electronic Materials Systems for Neuromorphic Computing

Abstract

Tuning electronic conductance through solid state electrochemical ion insertion has emerged as a promising technology to enable next-generation, ultralow energy computing architectures1-3. Unlike two-terminal non-volatile memory elements, the three-terminal redox transistor decouples the ‘write’ and ‘read’ operations using a ‘gate’ electrode to tune the conductance state through charge transfer reactions involving ion injection into the channel electrode through a solid-state electrolyte. The insertion of ions into the bulk of the channel acts to dope the material through a gradual composition modulation that leads up to thousands of finely spaced conductance levels (synaptic weights) with near-ideal analog behavior. These properties enable low-energy operation without compromising analog performance and non-volatility. However, the strong coupling of ionic and electronic processes sharply challenges our current understanding of solid-state electrochemical systems, particularly at decreasing dimensions and timescales relevant to computing technology. In my talk I will discuss the rich portfolio of challenging, exciting fundamental science questions about ion tunable electronic materials systems and how we can harness these to realize a new paradigm for low power neuromorphic computing. Fuller, E. J.; El Gabaly, F.; Leonard, F.; Agarwal, S.; Plimpton, S. J.; Jacobs-Gedrim, R. B.; James, C. D.; Marinella, M. J.; Talin, A. A., Li-Ion Synaptic Transistor for Low Power Analog Computing. Advanced Materials 2017, 29.Fuller, E. J.; Keene, S. T.; Melianas, A.; Wang, Z. R.; Agarwal, S.; Li, Y. Y.; Tuchman, Y.; James, C. D.; Marinella, M. J.; Yang, J. J.; Salleo, A.; Talin, A. A., Parallel programming of an ionic floating-gate memory array for scalable neuromorphic computing. Science 2019, 364 (6440), 570.Li, Y. Y.; Fuller, E. J.; Asapu, S.; Agarwal, S.; Kurita, T.; Yang, J. J.; Talin, A. A., Low-Voltage, CMOS-Free Synaptic Memory Based on LixTiO2 Redox Transistors. Acs Applied Materials & Interfaces 2019, 11 , 38982.