Mimicking Neurotransmitter Release and Long‐Term Plasticity by Oxygen Vacancy Migration in a Tunnel Junction Memristor. (26th June 2019)

• Record Type: Journal Article
• Authors: Tan, Hongwei; Majumdar, Sayani; Qin, Qihang; Lahtinen, Jouko; van Dijken, Sebastiaan
• Is Part Of: Advanced intelligent systems. Volume 1:Number 2(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-06-26
• Subjects: artificial synapses -- ionic interface -- long-term plasticity -- memristors -- neurotransmitter release -- octal memory -- oxide tunnel junction; Artificial intelligence -- Periodicals; Robotics -- Periodicals; Control theory -- Periodicals; 006.3
• DOI: 10.1002/aisy.201900036
• Languages: English
• ISSNs: 2640-4567

Abstract

Abstract : Activated by action potentials and Ca 2+ ion migration, neurotransmitters in biological synapses are released from vesicles at the presynaptic membrane to the cleft and bonded to receptors on the postsynaptic membrane. The bonded neurotransmitters modify the electrochemical properties of the postsynaptic membrane and, thereby, the synaptic plasticity, which forms the basis for learning, memory, emotion, cognition, and consciousness. Here, the oxygen vacancy transport in Au/SrTiO3 (STO)/La0.67 Sr0.33 MnO3 (LSMO) tunnel junctions is exploited to mimic neurotransmission processes in an artificial ionic electronic device. Using voltage pulses of varying number, amplitude, and polarity, it is demonstrated that reversible oxygen vacancy migration across the STO/LSMO interface provides stable multilevel resistance switching for octal memory devices and resembles the quantal, stochastic, and excitatory or inhibitory nature of neurotransmitter release dynamics. Moreover, fundamental synaptic behaviors including long‐term potentiation/depression and various types of spike‐timing‐dependent plasticity characteristics are emulated, opening a promising biorealistic approach to the design of neuromorphic devices. Abstract : Biorealistic emulation of a biological synapse is demonstrated using neurotransmission‐like oxygen vacancy transport in a tunnel junction memristor. Leveraging the vacancy release, capturing and storing capabilities of the oxide electrode and tunnel barrier, the conductivity of the junction is deliberately and reversibly tuned, enabling stable octal information storage and accurate emulation of long‐term plasticity for neuromorphic computing.