Modeling terahertz heterodyne detection based on photomixing

We present a simple model for continuous wave (CW) terahertz heterodyne detection based on photomixing. This model takes into account the antenna parameters as well as the properties of the substrate. Results from our analytical analysis can be used to obtain the appropriate values for the substrate parameters to maximize received THz signal. Focusing on the dipole antenna, we derive a simple expression for the current created by the THz field in terms of antenna length and parameters of the photomixer.