Integrating of continuous graphene with periodic ferroelectric domains for adaptive terahertz photodetector
Graphene plasmons hold immense potential for terahertz (THz) detector application due to their fascinating interactions between radiation and matter. However, it has remained challenging to excite and manipulate graphene plasmons within continuous graphene that is free of patterning technique. Here, we report an adaptive wavelength-sensitive terahertz detector consisting of continuous graphene integrated onto a ferroelectric thin film with periodic polarization domains. This designed device is capable of absorbing THz waves with zero input bias voltage because of highly confinement of surface plasmons within the interface between graphene and ferroelectrics. By reconfiguring an interweaving squared ferroelectric domain array with alternating upward and downward polarizations, our devices theoretically own an ultrahigh responsivity of 17.56 A W-1 and a specific detectivity of 1.11*10^11 Jones at room temperature. We also demonstrate that the photodetectors make possible for spectrum reconstruction application of portable spectrometer at a broad operation band of 4.97 to 7.85 THz with resolution up to 0.02 THz combining the mathematical algorithms.