UCLA

Terahertz optoelectronics have shown significant promise in the development and enhancement of technologies in chemical identification, biological sensing, and medical imaging. The practical advancement of such devices, however, has been hindered by the characteristics of the frequency range, 0.3 to 3 THz in the electromagnetic radiation spectrum. Presented here is a demonstration of the significant advancements possible in creating efficient and ultra-fast plasmonic THz sources by incorporating an optical cavity using a distributed Bragg reflector (DBR). Plasmonic electrodes enable increased transmission of photons into a GaAs photo-absorbing substrate, and the DBR enhances the quantum efficiency of the device by creating an optical cavity which allows for nearly 100\% of the incoming light getting absorbed in the active GaAs layer.