Increasing the bandwidth of planar on-chip THz devices for spectroscopic applications

We demonstrate an increase in bandwidth, from 600 GHz to 1.5 THz, of planar Goubau-line on-chip devices with integrated low-temperature-grown (LT) GaAs photoconductive (PC) switches, using a substrate-thinning technique. The effect of substrate thinning was investigated both experimentally and theoretically, and the increase in bandwidth then used for spectroscopy of overlaid polycrystalline materials.