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Abstract Terahertz technology has the potential to have a large impact in myriad fields, such as biomedical science, spectroscopy, and communications. Making these applications practical requires efficient, reliable, and low‐cost devices. Photoconductive switches (PCS), devices capable of emitting and detecting terahertz pulses, are a technology that needs more efficiency when working at telecom wavelength excitation (1550 nm) to exploit the advantages this wavelength offers. ErAs:InGaAs is a semiconductor nanocomposite working at this energy; however, high dark resistivity is challenging due to a high electron concentration as the Fermi level lies in the conduction band. To increase dark resistivity, ErAs:InGaAlBiAs material is used as the active material in a PCS detecting Terahertz pulses. ErAs nanoparticles reduce the carrier lifetime to subpicosecond values required for short temporal resolution, while ErAs pins the effective Fermi level in the host material bandgap. Unlike InGaAs, InGaAlBiAs offers enough freedom for band engineering to have a material compatible with a 1550 nm pump and a Fermi level deep in the bandgap, meaning low carrier concentration and high dark resistivity. Band engineering is possible by incorporating aluminum to lift the conduction band edge to the Fermi level and bismuth to keep a bandgap compatible with 1550 nm excitation. 

We present a Monte Carlo model that simulates the effects of non-equilibrium carrier-carrier scattering and the presence of layers of ErAs nanoislands in a GaAs terahertz antenna detector. To minimize computing time, we split the model into two simulations on numerical grids with optimized resolutions. First, we calculate the effects of the ErAs nanoislands on carrier lifetime in a high resolution volume of GaAs. We then incorporate those results into a larger, lower resolution, two-dimensional simulation that models the antenna detector. The computational results match experimental data presented by Kadow et al. [Appl. Phys. Lett. 75, 3548–3550 (1999)] and show that the lifetime of the carriers is closely linked to the periodicity of the nanoisland layers. Our results also highlight how the periodicity of the nanoisland layers affects the sensitivity and bandwidth of the terahertz detector, information that can be used to create custom devices with optimal parameters. 

Abstract The group III–V semiconductor photonic system is attractive to photonics engineers because it provides a complete set of photonic components. A plasmonic material that can be epitaxially integrated with the group III–V photonic system will potentially lead to many applications leveraging plasmonics and metamaterials. In this work, the shortest plasma wavelength ever reported in a III–V‐based material is demonstrated by epitaxially embedding ErAs into GaAs. This composite material acts as a tunable plasmonic material across the technologically important 2.68–6 µm infrared window. The growth window of this material is demonstrated to be much wider than other current heavily doped III–V plasmonic materials. Additionally, it is shown that the scattering rate can be reduced by increasing the growth temperature. The wide growth temperature range, designer plasmonic response, and the ease of epitaxial integration with other III–V semiconductor devices demonstrate the potential of ErAs:GaAs nanocomposites for the creation of a new type of metamaterial and other novel optoelectronic and nanophotonic applications.