Multilayer graphene and black phosphorus thin-film frequency doublers using direct-current bias

Multilayer graphene and black phosphorus films exhibit strong nonlinearity under voltage modulation. In this paper, according to the nonlinear characteristics of graphene and black phosphorus, the frequency doubling characteristics of graphene and black phosphorus are introduced, and the nonlinear SDD model of graphene is established in EDA, and the simulation results are basically consistent with the measured results. Under the regulation of DC bias voltage, the second harmonic output power of both graphene frequency doubler and black phosphorus frequency doubler is larger than their third harmonic output power when the operating frequency is 800–1100 MHz. The experimental results show that the minimum conversion loss of the black phosphorus multiplier is 24.22 dB when the input voltage is 0.9 V and the input power is 12 dBm, and the minimum conversion loss of the graphene multiplier is 32.15 dB when the input voltage is 1.6 V. The experimental results show that the conversion loss of the black phosphorus multiplier is better than that of the graphene multiplier, and the conversion efficiency is higher.