FDTD analysis of photoconducting antennas for millimeter‐wave generation

Abstract

In this paper, a hybrid numerical technique is presented for modeling a photoconducting antenna structure designed for optoelectronic generation of millimeter waves. The technique interfaces the solid-state device model with the three-dimensional ( ) ( ) 3D finite-difference time-domain FDTD method to achieve the active antenna modeling effectiveness and efficiency. The FDTD algorithm is applied to simulate the passive part of the antenna structure, whereas the numerical device simulation is employed to model the photoconductor that is illuminated by lasers. Physical performance of the photoconductor and response of the antenna are analyzed. Numerical results show good correlation with the experimental result and consequently demonstrate the feasibility of the full-wave modeling.

Exploring Dynamics in the Far-Infrared with Terahertz Spectroscopy

“…They also found that the THz waveform is distorted when detected with a photoconductive antenna. Similarly, Chen and co-workers employed FDTD methodology to model a photoconductive antenna, and found reasonable agreement with experimental measurements . THz emission from photoconductive antennas has also been modeled analytically by Duvillaret et al They evaluated the influence of parameters such as free carrier lifetime, carrier collision time, and optical pulse duration on the THz bandwidth, power, and signal-to-noise ratio.…”

“…This type of source is typically used with oscillator-only, i.e., nonamplified, systems, and there has only been a small amount of time-resolved work using this type of THz pulse generator. The generation of THz pulses in photoconductive antennas has been modeled numerically [27][28][29] and analytically. 30 A generic setup is shown in Figure 1.…”

“…Similarly, Chen and co-workers employed FDTD methodology to model a photoconductive antenna, and found reasonable agreement with ex- perimental measurements. 27 THz emission from photoconductive antennas has also been modeled analytically by Duvillaret et al 30 They evaluated the influence of parameters such as free carrier lifetime, carrier collision time, and optical pulse duration on the THz bandwidth, power, and signal-to-noise ratio. Malevich performed Monte Carlo simulations of THz generation from the semiconductor surface depletion field, and included acoustic, optical, and intervalley phonon scattering.…”

“…Naturally, most experimental papers include theory at the level of extracting dynamical information through an appropriate model, but this section concentrates on papers whose primary focus is theoretical in nature. These papers can be loosely grouped into three categories: (1) understanding generation and detection, typically in regard to photoconductive antennas, ,,,,,,− (2) issues related to THz pulse propagation, ,− and (3) understanding phenomena observed in specific types of THz experiments. ,,,− …”

Investigation of annular ring microstrip antenna using conformal mapping

“…Different parameters of the ARMA have also been investigated using Green's function method 11 . Besides, a number of rigorous investigations on ARMA have been done using different numerical techniques such as finite difference method, 12,13 finite element method, 14,15 method of moment, 16 etc. Those methods are very much time consuming and not suitable for a computer‐aided design package.…”