UTC-PD-integrated HEMT for optical-to-sub-terahertz carrier frequency down-conversion

We developed a novel InGaAs-channel high-electron-mobility transistor (HEMT) integrated with a uni-traveling-carrier photodiode (UTC-PD) structure for the optical-to-wireless carrier frequency down-conversion. We experimentally demonstrated that the output intensity of the down-converted signal is significantly enhanced by 34 dB compared with a standard HEMT, owning to the integration of the UTC-PD structure. We also verified the feasibility of the UTC-PDintegrated HEMT for practical use in the future full coherent network systems.