Modulation characteristics of uncooled graphene photodetectors

摘要

We report on the modulation characteristics of the uncooled terahertz (THz) and infrared (IR) detectors using uniform graphene layers (GLs) and perforated graphene layers (PGL). Our analysis shows that the PGL detectors could have more than an order of magnitude smaller dark current compared to more conventional GL reversed biased photodetectors operating in the same frequency range. The modulation mechanism for the simulated photodetectors is the variation of the density and effective temperature of the two-dimensional electron-hole plasma with the varying intensity of the THz or IR radiation. Our simulations predict a reasonable modulation depth up to the modulation frequencies of 50 GHz for the impinging radiation frequencies up to the mid-IR range.