Simulation of tuning graphene plasmonic behaviors by ferroelectric domains for self-driven infrared photodetector application
We demonstrate a tunable longwave infrared photodetector with ultra-high sensitivity based on graphene surface plasmon polaritons controlled by ferroelectric domains. The simulated results show the photodetector features a tunable absorption peak, modulated by periodically polarized ferroelectric domains at nanoscale, with an ultra-high responsivity up to 7.62×106 A W-1 and detectivity of ~6.24×1013 Jones (Jones = cm Hz^1/2 W-1) in the wavelengths ranging from 5 to 20 μm at room temperature. The potential mechanism for the prominent performances of the proposed photodetector can be attributed to the highly confined graphene surface plasmons excited by the local electrical field across the interface of graphene and ferroelectric layer resonant to the incident wavelength, which could be easily controlled by the features of the ferroelectric domains. Compared with the silicon-based graphene plasmonic photodetector using a complex process of micro-nano fabrication, the proposed photodetector provides the advantages of more convenient and controllable technique without need of patterning graphene, and lower energy consumption due to nonvolatile properties of the ferroelectrics free of additional contact electrode. The tunable spectral response and the ultra-high responsivity make the photodetector based on graphene plasmon tuned by the ferroelectric domains promising in practical applications of micro-spectrometer and other light sensing devices.