Mixed-Frequency Signal Processing Implemented by a Multi-Terminal Electrolyte-Gated Transistor-Based Physical Reservoir

Constructing highly compact and low hardware consuming multi-timescale physical reservoir is one of challenges in the hardware implementation of reservoir computing (RC) systems. However, state-of-the-art memristor-based reservoir layer based on ionic diffusion mechanisms suffers from relatively narrow temporal dynamic modulation window, limiting the multi-timescale feature extraction performance. In this letter, a proton-driven multi-terminal electrolyte-gated transistor (MTEGT) is proposed to obtain abundant reservoir states by ion-electron coupling through the multi-terminal modulation. The relaxation time of MTEGT ranges nearly two orders of magnitude (0.03 s to 1.0 s) within a 2.0 V bias voltage variation window (−1.2 V to 0.8 V). The MTEGT-based reservoir successfully modulates the amplitude of input signals at different frequencies. Moreover, a multiple superimposed oscillator task (MSO5 task) with five different frequencies is demonstrated with an ultralow normalized mean square error (NMSE) of 0.0009. This paves the way for the development of multi-timescale ion-controlled physical reservoirs with low hardware consumption and integration complexities.