An Accurate Circuit Model for Photoconductive Antennas

Fatemeh aghili; Ali Mahjoori

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arXiv · 1903.01984

An Accurate Circuit Model for Photoconductive Antennas

Fatemeh aghili·Ali Mahjoori

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Abstract

THz photoconductive antennas are among the most popular devices for THz wave generation and detection. A novel and accurate circuit is proposed to model the performance of such antennas, especially those which are frequency dependant. The suggested equivalent circuit consists of an external source voltage, a source input admittance, a loss resistance related to the electrode loss resistance, a frequency-dependant capacitance associated with capacitive behavior of the gap between the electrodes, and a controlled voltage dependant source representing the screening of photo-carriers. Based on this model, the radiation from a simple frequency dependent antenna, i.e. a dipole antenna, is investigated. Excellent agreement is observed between the obtained results by the proposed equivalent circuit model and those by measurement.

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Fatemeh aghili, Ali Mahjoori. 2019-03-02. An Accurate Circuit Model for Photoconductive Antennas. https://arxiv.org/abs/1903.01984

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