posted on 2023-12-08, 18:35authored byDeli Shi, Wenhui Wang, Yizheng Liang, Libing Duan, Guanghua Du, Yanbo Xie
The
emergence of nanofluidic memristors has made a giant leap to
mimic the neuromorphic functions of biological neurons. Here, we report
neuromorphic signaling using Angstrom-scale funnel-shaped channels
with poly-l-lysine (PLL) assembled at nano-openings. We found
frequency-dependent current–voltage characteristics under sweeping
voltage, which represents a diode in low frequencies, but it showed
pinched current hysteresis as frequency increases. The current hysteresis
is strongly dependent on pH values but weakly dependent on salt concentration.
We attributed the current hysteresis to the entropy barrier of PLL
molecules entering and exiting the Angstrom channels, resulting in
reversible voltage-gated open-close state transitions. We successfully
emulated the synaptic adaptation of Hebbian learning using voltage
spikes and obtained a minimum energy consumption of 2–23 fJ
in each spike per channel. Our findings pave a new way to mimic neuronal
functions by Angstrom channels in low energy consumption.