基于光子混频的 140∼220 GHz 噪声发生器

Abstract

A terahertz noise generator based on photo-mixing is proposed and implemented. Terahertz noise is generated by photo-mixing multiple incoherent lights from a super luminescent diode (SLD) through a Uni-Traveling-Carrier photodiode (UTC-PD). By optimizing the epitaxy layer structure and the electrode, the bandwidth of the UTC-PD exceeds 200 GHz. The packaged UTC-PD module exhibits a flat terahertz-wave output over the frequency range of 140∼220 GHz. Terahertz noise generation over the frequency range from 140 GHz to 220 GHz is demonstrated with an excess noise ratio (ENR) up to 35±4.6 dB. Furthermore, the ENR of the generated terahertz noise can be tuned by adjusting the input optical power.