Ferroelectric polarization modulated optoelectronic synapses based on BaTiO₃/TiO₂ heterojunction for non-volatile...

Area of Science:

• Materials Science
• Neuroscience
• Computer Engineering

Background:

• Neuromorphic computing architectures aim to mimic biological information processing.
• Optoelectronic synapses with multimodal neuromodulation are crucial for advanced artificial intelligence.
• Ferroelectric materials offer unique properties for non-volatile memory applications.

Purpose of the Study:

• To construct BaTiO3/TiO2 optoelectronic synaptic devices with enhanced non-volatile memory characteristics.
• To investigate the effect of interfacial energy band engineering and ferroelectric polarization on synaptic device performance.
• To demonstrate the application of these devices in artificial intelligence tasks like image recognition.

Main Methods:

• Fabrication of BaTiO3/TiO2 heterojunction synaptic devices.
• Interfacial energy band engineering for improved device performance.
• Modulation of synaptic plasticity through light pulse parameter adjustment.
• Ferroelectric polarization strategy to enhance memory retention.
• Convolutional neural network (CNN) implementation for dataset recognition.

Main Results:

• Achieved a 1350% enhancement in relaxation time (τ2) compared to conventional BaTiO3 devices.
• Demonstrated short-term to long-term memory conversion and simulated learning experiences.
• Downward ferroelectric polarization extended τ2 to 202.93 s with image retention exceeding 4800 s.
• Exhibited biological-level energy efficiency (10.45 fJ).
• Attained 97.5% and 89.05% recognition accuracy on MNIST and Fashion-MNIST datasets, respectively.

Conclusions:

• The BaTiO3/TiO2 heterojunction synaptic devices exhibit significant potential for artificial optoelectronic synapses.
• Interfacial engineering and ferroelectric polarization are effective strategies for enhancing synaptic device performance.
• These devices offer a viable platform for multimodal neuromorphic computing applications with high energy efficiency and accuracy.