Design of an Electrically Written and Optically Read Non-volatile Memory Device Employing BiFeO₃/Au Heterostructures with Strong Absorption Resonance

Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consumption is a significant issue for information technology. Here we design an 'electrically written and optically read' information storage device employing BiFeO₃/Au heterostructures with strong absorption resonance. The electro-optic effect is the basis for the device design, which arises from the strong absorption resonance in BiFeO₃/Au heterostructures and the electrically tunable significant birefringence of the BiFeO₃ film. We first construct a simulation calculation of the BiFeO₃/Au structure spectrum and identify absorption resonance and electro-optical modulation characteristics. Following a micro scale partition, the surface reflected light intensity of different polarization units is calculated. The results depend on electric polarization states of the BiFeO₃ film, thus BiFeO₃/Au heterostructures can essentially be designed as a type of electrically written and optically read information storage device by utilizing the scanning near-field optical microscopy technology based on the conductive silicon cantilever tip with nanofabricated aperture. This work will shed light on information storage technology.