Flexible biomimetic olfactory neurons based on organic heterojunction

Simulating the human olfactory nervous system is one of the key issues in the field of neuromorphic computing.Olfac-tory neurons interact with gas molecules,transmitting and storing odor information to the olfactory center of the brain.In order to emulate the complex functionalities of olfactory neurons,this study presents a flexible olfactory synapse transistor(OST)based on pentacene/C8-BTBT organic heterojunction.By modulating the interface between the energy bands of the organic semiconductor layers,this device demonstrates high sensitivity(ppb level)and memory function for NH3 sensing.Typi-cal synaptic behaviors triggered by NH_(3) pulses have been successfully demonstrated,such as inhibitory postsynaptic currents(IPSC),paired-pulse depression(PPD),long-term potentiation/depression(LTP/LTD),and transition from short-term depression(STD)to long-term depression(LTD).Furthermore,this device maintains stable olfactory synaptic functions even under differ-ent bending conditions,which can present new insights and possibilities for flexible synaptic systems and bio-inspired elec-tronic products.

InGaZnO-based photoelectric synaptic devices for neuromorphic computing

Photoelectric synaptic devices could emulate synaptic behaviors utilizing photoelectric effects and offer promising prospects with their high-speed operation and low crosstalk. In this study, we introduced a novel InGaZnO-based photoelectric memristor. Under both electrical and optical stimulation, the device successfully emulated synaptic characteristics including excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), long-term potentiation (LTP), and long-term depression (LTD). Furthermore, we demonstrated the practical application of our synaptic devices through the recognition of handwritten digits. The devices have successfully shown their ability to modulate synaptic weights effectively through light pulse stimulation, resulting in a recognition accuracy of up to 93.4%. The results illustrated the potential of IGZO-based memristors in neuromorphic computing, particularly their ability to simulate synaptic functionalities and contribute to image recognition tasks.

Organic heterojunction synaptic device with ultra high recognition rate for neuromorphic computing

Traditional computing structures are blocked by the von Neumann bottleneck,and neuromorphic computing devices inspired by the human brain which integrate storage and computation have received more and more attention.Here,a flexible organic device with 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene(C8-BTBT)and 2,9-didecyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene(C10-DNTT)heterostructural channel having excellent synaptic behaviors was fabricated on muscovite(MICA)substrate,which has a memory window greater than 20 V.This device shows better electrical characteristics than organic field effect transistors with single organic semiconductor channel.Furthermore,the device simulates organism synaptic behaviors successfully,such as paired-pulse facilitation(PPF),long-term potentiation/depression(LTP/LTD)process,and transition from short-term memory(STM)to long-term memory(LTM)by optical and electrical modulations.Importantly,the neuromorphic computing function was verified using the Modified National Institute of Standards and Technology(MNIST)pattern recognition,with a recognition rate nearly 100%without noise.This research proposes a flexible organic heterojunction with the ultra-high recognition rate in MNIST pattern recognition and provides the possibility for future flexible wearable neuromorphic computing devices.

A high-speed 2D optoelectronic in-memory computing device with 6-bit storage and pattern recognition capabilities

The explosively developed era of big-data compels the increasing demand of nonvolatile memory with high efficiency and excellent storage properties.Herein,we fabricated a high-speed photoelectric multilevel memory device for neuromorphic computing.The novel two-dimensional(2D)MoSSe with a unique Janus structure was employed as the channel,and the stack of Al_(2)O_(3)/black phosphorus quantum dots(BPQDs)/Al_(2)O_(3)was adopted as the dielectric.The storage performance of the resulting memory could be verified by the endurance and retention tests,in which the device could remain stable states of programming and erasing even after 1,000 cycles and 1,000 s.The multibit storage could be realized through both different voltage amplitudes and pulse numbers,which could achieve 6 bits(64 distinguishable levels)under pulse width of 50 ns.Furthermore,our memory device also could realize the simulations of synapses in human brain with optical and electric modulations synergistically,such as excitatory post-synaptic current(EPSC),long-term potentiation/depression(LTP/LTD),and spike-timing-dependent plasticity(STDP).Neuromorphic computing was successfully achieved through a high recognition of handwritten digits up to 92.5%after 103 epochs.This research is a promising avenue for the future development of efficient memory and artificial neural network systems.