Capability of THz sources based on Schottky diode frequency multiplier chains

We have developed and tested a number of fixed-tuned GaAs Schottky diode frequency doubler and tripler designs covering over 50% of the 100 - 2000 GHz band, with best measured 120 K peak efficiencies ranging from 39% for a 190 GHz doubler to 0.94% for 1800 GHz tripler. We find that the efficiencies across this broad range of frequency and performance can be well-described by a simple empirical exponential decay model. This model can be used to predict achievable performance for Schottky diode frequency multipliers and multiplier chains, and gives an indication of what chain configurations are most likely to produce optimal results to reach a given frequency range. Extrapolating the models beyond the highest frequencies tested predicts that cooled Schottky diode frequency multiplier chains are capable of producing at least 1 μW at 2.5 THz.