Terahetz homodyne spectroscopy system based silicon photonic integrated circuit

Abstract

We present a homodyne terahertz spectroscopy system consisting of a broadband uni-travelling carrier photodiode, photoconductive antenna, and silicon photonic integrated circuit for the homodyne detection. Millimeter-scale silicon photonic circuits greatly reduce the impact of the environment temperature fluctuations on coherency between probe and reference signals and enable reliable measurement of the phase information of samples under test at up to 1 THz.