Application | Junction structure | Main mechanism | Array | (Local) circuit complexity | Specific functions | Targeted task | Pros/Cons | Refs. |
---|---|---|---|---|---|---|---|---|
Artificial synapses | Planar device LixMos2 with Au contacts | Phase transition | – | – | Synaptic plasticity and competition/cooperation | Bio-realistic functionality | Bio-realistic/planar device (low-scalable) | [119] |
Pt/Ta2O5/Nb2O5−x/Al2O3−y/Ti | Electron trapping/detrapping | 32 × 32 | – | Long-term potentiation and depression | MNIST dataset recognition | Uniformity/High operation voltage | [90] | |
Ag/BaTiO3/Nb:SrTiO3 | Ferroelectric polarization | – | – | Spike timing dependent plasticity | – | Ultrafast operation/CMOS incompatible (PLD) | [106] | |
PT/α-MoO3/SrCoO2.5/Nb:SrTiO3 | Phase transition | – | – | Long-term potentiation and depression | MNIST dataset recognition | Linear IV relationship/Large temperature dependency | [126] | |
Artificial neurons | Pt/anodized TiOx/Ti | Ion migration (VO) | 20 × 20 | A resistor and a capacitor | Short-term memory, self-rectification, LIF | AMP sequence generation | Uniformity/Small ON/OFF ratio | [57] |
Au/MAPbI3/ITO | Ion migration (VI) | 2 × 2 | 1 memristor, 3 resistors, 1 capacitor, 2 potentiometers, 1 comparator, 1 pulse generator | Short-term memory, LIF | SNN demonstration | Low operation voltage/CMOS incompatible (halide perovskite) | [59] | |
W/Pr0.7Ca0.3MnO3/Pt | Filling-controlled Mott transition | 16 × 3 (simulation) | 1 memristor with an external measurement and pulse input system | LIF | Fisher’s iris dataset classification | Tunable firing frequency/Insufficient physical demonstration | [153] | |
W/WO3/PEDOT:PSS/Pt | Ion migration (proton) | – | 2 memristors, 5 resistors, 1 capacitor, 3 potentiometers, 1 comparator, 1 timer | LIF | – | Highly bio-realistic HH neuronal dynamics/Circuit complexity | [155] | |
Reservoir computing | Au/WOx/W | Ion migration (VO) | (88 out of) 32 × 32 | Physical reservoir measured by PCB | Short-term memory, memristor dynamics | MNIST dataset classification, second-order nonlinear prediction, spoken-digit recognition, Mackey–glass prediction | Uniformity/Slow resistance change | |
Ti/TiOx/TaOy/Pt | Ion migration (VO) | – | Physical reservoir measured by PCB | Short-term memory, memristor dynamics | Waveform classification, spoken-digit recognition, time-series prediction | Uniformity/Small dynamic current change | [31] | |
Planar device SnS with Cr contacts | Electron trapping/detrapping | 5 × 1 | Physical reservoir | Optoelectronic signal, memristor dynamics | Korean characters and sentence recognition | Ability of optoelectronic signal processing/Small dynamic current change | [23] | |
Selector | Pt/CoO/ITO | Electron trapping/detrapping | – | 1 selector(memristor) with wire-connected resistive switching memory | Threshold switching | – | Uniformity/Slow operation speed | [93] |
Self-rectifying memristor | Pt/TaOy/nanoporous TaOx/Ta | Ion migration (VO) | 16 × 16 | – | Self-rectification, long-term potentiation and depression | MNIST dataset recognition | Uniformity/High operation voltage | [63] |
Pt/Al2O3/HfO2/Ti | Electron trapping/detrapping | 64 × 64 | – | Self-rectification, long-term potentiation and depression | MNIST dataset recognition | Uniformity/Low programmability | [182] | |
Ru/Hf0.8Si0.2O2/Al2O3/Hf0.5Si0.5O2/TiN | Ion migration (VO) | 30 × 30 | – | Self-rectification, long-term potentiation and depression | Vector–Matrix Multiplication | Uniformity/Small ON/OFF ratio | [183] | |
Pd/HfO2/WOx/W | Ion migration (VO) | – | – | Self-rectification, long-term memory | – | Uniformity/High operation voltage | [184] |