A Tunable Fano Resonator with High Sensitivity Based on Black Phosphorus in the Terahertz Band

A Fano resonator using black phosphorus, capable of tuning the operating band while possessing high sensitivity, is proposed. A ring and a groove are respectively etched above and below the main channel to produce the Fano resonance, resulting in a highly sensitive Fano resonator. Such a sensor can capture slight changes in the surrounding environment. Moreover, adding black phosphorus into the ring above the channel and into the groove below the channel, the electron doping of black phosphorus can be altered to adjust the resonant frequency of the Fano resonator. The shiftable frequency of the Fano resonator designed herein can reach 57 GHz at the second-order resonance around 1.895 THz, an ability highly attractive in fields that require high sensitivity and adjustability. It is essential in the area of integrated electronics, offers fresh perspectives for innovations in integrated electronic gadgets, and paves the way for flexible terahertz systems.