Ferroelectric superdomain controlled graphene plasmon for tunable mid-infrared photodetector with dual-band spectral selectivity

Dual-band infrared photodetectors (DBIPs) can discriminate desired signals from complex scenes and thus are highly expected for threat-warning, remote sensing, and astronomy applications. Conventional DBIPs with high performances are, however, typically based on semiconductor thin films, but remain the challenges of expensive growth and cooling requirements. Here, we report a room-temperature graphene plasmonic photodetector with tunable dual-band infrared spectral selectivity driven by ferroelectric superdomain. The periodic ferroelectric polarization array with nanoscale ring shapes provides an ultrahigh electrostatic field for spatially doping of monolayer graphene to desired patterns, and is further used to excite and confine intrinsic graphene plasmons. Our devices exhibit tunable resonance photoresponse in both two bands of 3.7–16.3 μm and 15.1–52.1 μm. The numerical calculations show that our devices own ultrahigh responsivities of 667–1080 A W −1 at room temperature in the range of 5–50 μm. Our devices make possible the applications of the infrared imaging system and both stationary and motion states of objects detection. These investigations provide a novel approach for advanced infrared system construction by employing a simple, low-cost, uncooled multispectral detectors array.