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Updated: Jun 13, 2026
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Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
Terahertz emission from lateral photo-Dember currents.
1Department of Physics and Center for Applied Photonics, University of Konstanz 78457, Germany.
Optics Express
|April 15, 2010
Summary
The photo-Dember effect generates terahertz (THz) radiation from ultrafast electron-hole separation. A new method orients these currents parallel to the surface, enhancing THz emission efficiency and bandwidth for semiconductor devices.
Area of Science:
- Terahertz (THz) Science and Technology
- Semiconductor Physics
- Optoelectronics
Background:
- The photo-Dember effect causes THz emission via ultrafast carrier separation in semiconductors.
- Current THz emission is inefficiently coupled due to polarization perpendicular to the surface.
Purpose of the Study:
- To propose and demonstrate a novel scheme for generating photo-Dember currents parallel to the excited surface.
- To enhance the directionality and efficiency of THz radiation emission.
Main Methods:
- Generating strong carrier gradients parallel to the surface in GaAs and In(0.53)Ga(0.47)As.
- Utilizing femtosecond pulsed optical excitation.
- Multiplexing phase-coherent photo-Dember currents by tailoring spatial carrier distribution.
Main Results:
- Demonstrated THz emission from photo-Dember currents oriented parallel to the surface.
- Achieved higher bandwidth THz emitters compared to traditional photoconductive emitters.
- Obtained THz electric field amplitudes comparable to high-efficiency biased emitters through multiplexing.
Conclusions:
- The proposed scheme effectively enhances THz emission directionality and efficiency.
- Photo-Dember THz emitters offer a promising alternative with superior bandwidth performance.
- Multiplexing technique significantly boosts THz emission strength.
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