Photo-Assisted Ferroelectric Domain Control for α-InSe Artificial Synapses Inspired by Spontaneous Internal Electric Fields.

α-InSe semiconductor crystals realize artificial synapses by tuning in-plane and out-of-plane ferroelectricity with diverse avenues of electrical and optical pulses. While the electrically induced ferroelectricity of α-InSe shows synaptic memory operation, the optically assisted synaptic plasticity in α-InSe has also been preferred for polarization flipping enhancement. Here, the synaptic memory behavior of α-InSe is demonstrated by applying electrical gate voltages under white light.

Gate-Tuned Gas Molecule Sensitivity of a Two-Dimensional Semiconductor.

In this work, we develop a gate-tunable gas sensor based on a MoS/hBN heterostructure field effect transistor. Through experimental measurements and numerical simulations, we systematically reveal a principle that relates the concentration of the target gas and sensing signals (Δ/) as a function of gate bias. Because a linear relationship between Δ/ and the gas concentration guarantees reliable sensor operation, the optimal gate bias condition for linearity was investigated.