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Updated: Aug 14, 2026

10:54
Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
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Terahertz photoconductive switch from GaAs grown on Ge substrate
Optics Express
|February 20, 2026
Summary
This study fabricates novel photoconductive terahertz switches using gallium arsenide (GaAs) on germanium (Ge) substrates, achieving broadband terahertz generation potential by overcoming bandwidth limitations.
Area of Science:
- Solid State Physics
- Terahertz Science and Technology
- Semiconductor Device Fabrication
Background:
- Conventional terahertz (THz) switches face bandwidth limitations.
- Germanium (Ge) offers broader THz transmission compared to traditional substrates.
- Gallium Arsenide (GaAs) is a key material for photoconductive switches.
Purpose of the Study:
- To fabricate and characterize novel photoconductive terahertz switches.
- To leverage Ge substrates for enhanced THz bandwidth.
- To investigate the impact of GaAs layer thickness on device performance.
Main Methods:
- Fabrication of GaAs epitaxial layers on Ge substrates.
- Characterization of device performance including breakdown fields and dark currents.
- Analysis of emitted terahertz spectra.
Main Results:
- Demonstrated potential for broadband THz generation using GaAs/Ge devices.
- Investigated the influence of GaAs layer thickness on key device parameters.
- Observed unforeseen charge transport phenomena.
Conclusions:
- GaAs/Ge photoconductive switches show promise for broadband THz applications.
- Device performance is influenced by GaAs layer thickness.
- Further research into charge transport mechanisms can optimize future devices.
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