Light sensitive memristor with bi-directional and wavelength-dependent conductance control

Abstract

We report the optical control of localized charge on positioned quantum dots in an electro-photo-sensitive memristor. Interband absorption processes in the quantum dot barrier matrix lead to photo-generated electron-hole-pairs that, depending on the applied bias voltage, charge or discharge the quantum dots and hence decrease or increase the conductance. Wavelength-dependent conductance control is observed by illumination with red and infrared light, which leads to charging via interband and discharging via intraband absorption, respectively. The presented memristor enables optical conductance control and may thus be considered for sensory applications in artificial neural networks as light-sensitive synapses or optically tunable memories. a) Corresponding

UV induced resistive switching in hybrid polymer metal oxide memristors

“…Moreover, resistive switching has been demonstrated in various configurations; ethanol-adsorbed ZnO thin film upon visible light activation 5 , ultra-thin hafnium-oxide 6 , multiferroic thin film memristors 7 , ITO/oxide devices 8 , as well as in RRAM devices through combination of light and electrical stimuli using a thin SiO x layer sandwiched between a transparent top electrode and a p-type Si substrate 9 . Furthermore, other configurations involving various nanostructures like semiconductor quantum dots, nano-rods and Metal-Insulator-Semiconductor structures have been studied for lightcontrolled resistive switching [10][11][12][13][14] or enhancement of the resistance of a conducting filament in the dielectric 15 .…”

Mimicking of pulse shape-dependent learning rules with a quantum dot memristor

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Photonic Synapses for Ultrahigh‐Speed Neuromorphic Computing

“…Furthermore, synaptic potentiation can be implemented with light pulses, whereas synaptic depression can only be realized with electrical pulses. It is worth mentioning that Hartmann and co‐workers developed a four‐terminal photoelectric device based on an InAs quantum dot‐doped GaAs/AlGaAs heterostructure . The device conductance can be reversibly adjusted by optical pulses indicating its possible application to photoelectric synapses.…”