Optoelectronic memristor for neuromorphic computing

With the need of the internet of things,big data,and artificial intelligence,creating new computing architecture is greatly desired for handling data-intensive tasks.Human brain can simultaneously process and store information,which would reduce the power consumption while improve the efficiency of computing.Therefore,the development of brainlike intelligent device and the construction of brain-like computation are important breakthroughs in the field of artificial intelligence.Memristor,as the fourth fundamental circuit element,is an ideal synaptic simulator due to its integration of storage and processing characteristics,and very similar activities and the working mechanism to synapses among neurons which are the most numerous components of the brains.In particular,memristive synaptic devices with optoelectronic responding capability have the benefits of storing and processing transmitted optical signals with wide bandwidth,ultrafast data operation speed,low power consumption,and low cross-talk,which is important for building efficient brain-like computing networks.Herein,we review recent progresses in optoelectronic memristor for neuromorphic computing,including the optoelectronic memristive materials,working principles,applications,as well as the current challenges and the future development of the optoelectronic memristor.

Intrinsic vacancy in 2D defective semiconductor In_(2)S_(3)for artificial photonic nociceptor

It is crucial to develop an advanced artificially intelligent optoelectronic information system that accurately simulates photonic nociceptors like the activation process of a human visual nociceptive pathway.Visible light reaches the retina for human visual perception,but its excessive exposure can damage nearby tissues.However,there are relatively few reports on visible light–triggered nociceptors.Here,we introduce a two-dimensional natural defectiveⅢ–Ⅵsemiconductorβ-In_(2)S_(3)and utilize its broad spectral response,including visible light brought by intrinsic defects,for visible light–triggered artificial photonic nociceptors.The response mode of the device,under visible light excitation,is very similar to that of the human eye.It perfectly reproduces the pain perception characteristics of the human visual system,such as‘threshold,’‘relaxation,’‘no adaptation’,and‘sensitization’.Its working principle is attributed to the mechanism of charge trapping associated with the intrinsic vacancies in In_(2)S_(3)nanosheets.This work provides an attractive material system(intrinsic defective semiconductors)for broadband artificial photonic nociceptors.

Thickness-dependent and strain-tunable magnetism in twodimensional van der Waals VSe_(2)

Two-dimensional(2D)van der Waals(vdW)magnetic materials with reduced dimensionality often exhibit unexpected properties compared to their bulk counterparts.In particular,the mechanical flexibility of 2D structure,enhanced ferromagnetism at reduced layer thickness,as well as robust perpendicular magnetic anisotropy are quite appealing for constructing novel spintronic devices.The vdW vanadium diselenide(VSe_(2))is an attractive material whose bulk is paramagnetic while monolayer is ferromagnetic with a Curie temperature(Tc)above room temperature.To explore its possible device applications,a detailed investigation on the thickness-dependent magnetism and strain modulation behavior of VSe_(2)is highly demanded.In this article,the VSe_(2)nanoflakes were controllably prepared via chemical vapor deposition(CVD)method.The few-layer single VSe_(2)nanoflakes were found to exhibit magnetic domain structures at room temperature.Ambient magnetic force microscopy(MFM)phase images reveal a clear thickness-dependent magnetism and the MFM phase contrast is traceable for the nanoflakes of layer thickness below~6 nm.Moreover,applying strain is found efficient in modulating the magnetic moment and coercive field of 2D VSe_(2)at room temperature.These results are helpful for understanding the ferromagnetism of high temperature 2D magnets and for constructing novel straintronic devices or flexible spintronic devices.