학술논문

Time-Domain Modelling of Pulsed Photoconducting Sources—Part II: Characterization of an LT GaAs Bow-Tie Antenna
Document Type
Periodical
Source
IEEE Transactions on Antennas and Propagation IEEE Trans. Antennas Propagat. Antennas and Propagation, IEEE Transactions on. 71(3):2536-2545 Mar, 2023
Subject
Fields, Waves and Electromagnetics
Aerospace
Transportation
Components, Circuits, Devices and Systems
Optical pulses
Optical saturation
Gallium arsenide
Optical variables measurement
Optical sensors
Optical receivers
Antennas
Equivalent circuit
photoconductive antennas (PCAs)
terahertz (THz)
THz radiated power
THz sources
THz technology
Language
ISSN
0018-926X
1558-2221
Abstract
Drude’s description of the response of low-temperature gallium arsenide to optical pulse excitation is used to evaluate the components of a time-domain Norton equivalent circuit of a photoconductive antenna (PCA) source. The saturation of the terahertz (THz) radiated power occurring at large optical excitation levels was previously associated by the scientific community to radiation and charge screening of the bias. With the present circuit, we are able to model accurately the measured saturation as only due to the EM feedback from the antenna to the bias. The predicted THz radiated power is shown to match very accurately the measurements when the circuit is combined with an accurate description of the experimental conditions and the modeling of the THz quasi-optical (QO) channel.