A power-free graphene mid-infrared photodetector array 后印本

摘要: Graphene plasmons can resonantly enhance the incident light absorption and offer a potential for tunable spectral selectivity for mid-infrared (MIR) detection. High-performance tunable graphene plasmonic devices are, however, typically based on electrode-patterned graphene, which requires high power input and are technologically challenging in compact assembly. Here we demonstrate a tunable MIR photodetector array operating at zero input bias voltage. Our devices consist of integrating monolayer graphene with periodically "type-printed" ferroelectric superdomain. The spatial graphene carrier density patterns can be readily modulated by artificially defined ferroelectric superdomain with periodic nanoscale-wide stripe domains, achieving nonuniform pattering of conductivity and subsequently enabling graphene plasmons excitation and confinement for a selective transmission resonance in MIR regime. A high photoresponsivity of ~30 mA W-1 at room temperature is achieved in our device. We also observe that our device array features a tunable detection performance with spectral selectivity from 7.2 to 8.5 {\mu}m by directly reconfiguring the periodicity of ferroelectric superdomain. Our strategy could lead to the development of smart fabrication of on-chip MIR photodetector array for application of tunable spectral systems with low-energy consumption.