Use of Gain Non-Linearities in Two-Terminal Edge-Coupled InGaAs/InP Heterojunction Phototransistors

We use the gain non-linearities at low optical power of edge coupled InGaAs/InP Heterojunction Bipolar Phototransistor to mix the optical demodulation products of two (or more) laser beams. One beam could be CW or low frequency range modulated since the other one is RF or microwave modulated. Relative experiments carried out for 2GHz and 2kHz show the mixing of the two demodulated electrical signals in the phototransistor.