Graphene/silicon heterojunction for reconfigurable phase-relevant activation function in coherent optical neural networks

Graphene/silicon heterojunction for reconfigurable phase-relevant activation function in coherent optical neural networks

Blog Article

Abstract Optical neural networks (ONNs) herald a new era in information and communication technologies and have implemented various intelligent applications.In an ONN, the activation function (AF) is a crucial component determining the network performances and on-chip AF devices are still in development.Here, we first demonstrate on-chip reconfigurable AF the gel bottle cashmere devices with phase activation fulfilled by dual-functional graphene/silicon (Gra/Si) heterojunctions.With optical modulation and detection in one device, time delays are shorter, energy consumption is lower, reconfigurability is higher and the device footprint is smaller than other on-chip AF strategies.The experimental modulation voltage (power) of our Gra/Si heterojunction achieves as low as 1 V (0.

5 mW), superior to many pure silicon counterparts.In the photodetection aspect, a high responsivity of over 200 mA/W is realized.Special nonlinear functions generated are fed into a complex-valued ONN to challenge handwritten letters and image recognition tasks, showing improved accuracy and potential of high-efficient, all-component-integration on-chip ONN.Our results offer new insights for on-chip ONN devices and pave the way to high-performance integrated bushranger awning optoelectronic computing circuits.