Twin tunable laser system with wavelength calibration for Tera-Hertz spectrometer

In this study, a laser beat system based on two DBR tunable lasers was bulid. The laser output wavelength is calibrated by the wavelength calibration device, in order to get the precise beat frequency. Finaly, we demonstrated a Tera-Hertz spectrometer using this two laser beat light source. This beat laser system has the advantages of low-cost, easy access, and fast wavelength tuning.