Controlling Long-Term Plasticity in Neuromorphic Computing Through Modulation of Ferroelectric Polarization.

Area of Science:

• Materials Science
• Neuroscience
• Computer Engineering

Background:

• Electrolyte-gated transistors (EGTs) show promise for neuromorphic computing by mimicking neurotransmission.
• Achieving long-term plasticity (LTP) in EGTs is challenging due to rapid electric double-layer (EDL) depolarization.
• Existing research on ferroelectric materials for synaptic devices primarily focuses on biological functions, neglecting nonvolatile memory applications.

Purpose of the Study:

• To develop a polyvinylidene fluoride (PVDF)-based ion-gel synaptic device capable of implementing LTP.
• To investigate the impact of ferroelectric materials on nonvolatile memory properties in synaptic devices.
• To demonstrate the potential of this device for neuromorphic computing applications.

Main Methods:

• Fabrication of a synaptic device using polyvinylidene fluoride (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) ion gel.
• Utilizing the residual polarization of PVDF-based polymers to control ion adsorption and slow anion escape.
• Implementing and testing synaptic functions such as LTP, paired pulse facilitation (PPF), high-pass filtering, and neurotransmitter control.

Main Results:

• The PVDF-based synaptic device successfully demonstrated LTP by controlling ion adsorption.
• The device exhibited key synaptic functions, including PPF, high-pass filtering, and neurotransmitter control.
• High recognition rates were achieved in artificial/convolutional neural network (A/CNN) simulations using ferroelectric polarization for LTP/D.

Conclusions:

• Introduction of PVDF-based polymers into the dielectric layer provides a rational strategy for ion adsorption via ferroelectric polarization.
• The developed synaptic device shows significant potential for advancing neuromorphic computing and nonvolatile memory technologies.
• This work bridges the gap between ferroelectric material research and practical synaptic device applications.