Two-dimensional Layered Materials for Artificial Synapse

We discuss the unique opportunities of introducing emerging two-dimensional (2D) materials as the fundamental building blocks for neuromorphic computing, namely synaptic devices, because of their remarkable scalability, transferability, flexibility, and photosensitivity. The 2D synaptic devices based on various mechanisms including charge storage, resistive switching and ferroelectricity are reviewed and compared. Additionally, the new research forefront on optical synaptic devices is introduced.