Continuous-Wave Electro-Optic Terahertz Dual-Comb Operating from 0.096 to 0.496 THz Using ErAs:In(Al)GaAs Photoconductors

An absolute-frequency terahertz (THz) dual-comb system was implemented using only standard telecom components, such as continuous-wave (CW) single mode lasers, optical modulators, and erbium-doped fiber amplifiers (EDFAs) for driving a pair of ErAs:In(Al)GaAs photoconductors. The dual-comb center frequency was tuned between 0.09596 and 0.49596 THz while the mode spacing was kept at 0.5 GHz, although any other lower frequency was also possible.