Solution-processed inorganic δ-phase CsPbI₃ electronic synapses with short- and long-term plasticity in a crossbar...

Area of Science:

• Materials Science
• Neuroscience
• Computer Engineering

Background:

• Memristive devices offer potential for neuromorphic computing by mimicking biological synapses.
• Halide perovskites show promise for artificial synapses due to their properties and fabrication methods.
• Chemical and phase instability of halide perovskites limit their practical application.

Purpose of the Study:

• To develop stable artificial synapses using a non-halide perovskite material.
• To investigate the synaptic characteristics and performance of these artificial synapses.
• To address the stability concerns associated with halide perovskite-based devices.

Main Methods:

• Fabrication of artificial synapses using a single-step spin-coating method.
• Utilizing fully inorganic nonperovskite δ-phase CsPbI3 in a cross-bar array architecture.
• Characterization of device performance, including ON/OFF ratio, endurance, and operation voltage.

Main Results:

• Artificial synapses demonstrated superior ambient stability (>90 days).
• The devices exhibited threshold switching with a moderate ON/OFF ratio, low operation voltage (0.3 V), and high endurance (>5 × 105).
• Emulation of synaptic functions including short-term plasticity, paired-pulse facilitation, and memory transition was achieved with a high signal-to-noise ratio (>102).

Conclusions:

• This study reports the first artificial synapses based on nonperovskite CsPbI3, achieving excellent ambient stability.
• The developed devices show promising performance for neuromorphic computing applications, overcoming halide perovskite limitations.
• This work paves the way for low-cost, high-density practical synapse arrays.