Light Assisted Electro-Metallization in Resistive Switch with Optical Accessibility

Abstract

An optically assisted electrically writable non-volatile nanophotonic resistive switch based on silicon is proposed with an optical readout capability. The proposed scheme also address the issue of undesired current overshoot in resistive switches. Optical assistance is provided with the blue pump light which leads to the photogenrated charge carriers in the active TiO_{2} layer to lower the set voltage and to improve the endurance of the device. A large hysteresis of the current loop in presence of a blue wavelength of light at lower voltages is observed with the proposed three-layered device of Ag/TiO_{2}/p-Si. The electrical resistive state of the device is readout at 1550-nm of wavelength with an optical extinction ratio of 16 dB for 1 mm long device. The optical guidance with the formation (low resistance state) and dissolution (high resistance state) of conductive path filament in the active layer of TiO_{2} is also discussed. The proposed nanophotonic functionality can be useful in realizing ultra-compact on-chip devices for optical switching, modulation and neuromorphic computing. © 1983-2012 IEEE.