Comparative study of equivalent circuit models for photoconductive antennas


Comparative study of equivalent circuit models for photoconductive antennas

Castañeda-Uribe, O. A.; Criollo, C. A.; Winnerl, S.; Helm, M.; Avila, A.

Comparison of equivalent circuit models (ECM) for photoconductive antennas (PCA) represents a challenge due to the multiphysics phenomena involved during PCA operation and the absence of a standardized validation methodology. In this work, currently reported ECMs are compared using a unique set of simulation parameters and validation indicators (THz waveform, optical power saturation and ECM voltages consistency). The ECM simulations are contrasted with measured THz pulses of an H-shaped 20μm gap PCA at different optical powers (20mW to 220mW). In addition, an alternative two-element ECM that accounts for both space-charge and radiation screening effects is presented and validated using the proposed methodology. The model shows an accurately reproduced THz pulse using a reduced number of circuital elements, which represents an advantage for PCA modeling.

Keywords: THz emitters; photoconductive emitter; equivalent circuit model

Permalink: https://www.hzdr.de/publications/Publ-27950
Publ.-Id: 27950