Towards Thz Beam Steering With Integrated Phased Photomixer Arrays

This paper presents the necessary building blocks towards the realization of on-chip, lens-free, spectrally selective, THz beam steering. We demonstrate continuous wave (CW) THz generation up to 2.2 THz by photomixing using antenna-coupled silicon-integrated germanium photodiodes, which reach an optical-to-THz conversion efficiency of about 1% at 100 GHz. We show THz beam forming within a small antenna array and address key challenges towards the realization of large quasi-optical THz phased arrays, by demonstrating low-loss (<0.2 dB/cm), low phase error routing and optical beam steering within hybrid Si/SiN optical phased arrays. Finally, we present an anti-reflection structure enabling lensfree THz beam steering.