Terahertz Frequency Quadrupler Based on a 2×2 Single-chip GaAs Monolithic Integration

In this paper, a 340GHz 2 × 2 single-chip quadrupler based on the GaAs monolithic integration has been designed. The whole 2*2 quadrupler includes two GaAs double chips integrated with eight diodes and six diodes on the 15um GaAs substrate respectively. The independent two DC biases are loaded onto the diode pairs of different chips through the corresponding low-pass filter, which is also integrated on the GaAs chip. The two GaAs substrates are glued into the waveguide slots with little conductive adhesive, and the beam fixed the diode pairs. Simulation result shows that this quadrupler delivers >40-mW output power and >15% conversion efficiency ranged from 325GHz to 355GHz with a 250-mW driven power. The peak power is 50-mW in 353GHz with almost 20% efficiency.