Integrated graphene/ferroelectric based plasmonic random access memory

Abstract

Using ferroelectric domains in lead zirconate titanate (PZT: PbZr0.3Ti0.7O3), we propose and simulate a graphene/ferroelectric-based integrated plasmonic random access memory (P-RAM). The proposed P-RAM poses bistable behavior between two transmission levels when the polarization of the ferroelectric film is switched via tuning an applied bias. Simulation results show that when a voltage applied to a 500-nm long P-RAM is swept from −1.5 V to +6 V and vice versa, the possible extinction ratio is about 18 dB. This integrated P-RAM, operating at a wavelength of 7 µm, can be used as a memory by measuring two distinct levels of transmission. The proposed integrated memory device, also functioning as a latching plasmonic switch, does not require any external unit for generating the required plasmonic wave. In the ON state, the wavelength of the plasmonic mode prorating across the memory unit is ∼156 nm. Its corresponding propagation length (∼5.57 μm) is longer than two-and-a-half times the entire P-RAM length. This proposed integrated P-RAM of footprint 2 μm2 that does not suffer from coupling loss is a promising device for applications in the storage of information and the development of future plasmonic chips. To obtain the presented numerical results, we solve the full Maxwell equations, by the 3D finite element method using the COMSOL multiphysics.