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Updated: Dec 21, 2025
10:54
Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
15.2K
Terahertz emission by multiple resonances under external periodic electrostatic field.
Divya Singh1, Hitendra K Malik2
1Department of Physics & Electronics, Rajdhani College, University of Delhi, New Delhi 110015, India.
Physical Review. E
|May 20, 2020
Summary
Collisional effects hinder terahertz (THz) radiation. Applying an external electric field in plasma enhances THz emission by generating new currents and enabling tunable resonance conditions.
Area of Science:
- Plasma physics
- Electromagnetic wave generation
- Nonlinear phenomena
Background:
- Collisional effects (ν≥0.5ωp) adversely impact terahertz (THz) radiation efficiency.
- Plasma frequency (ωp) is a critical parameter in understanding collisional effects.
Purpose of the Study:
- To propose a method for efficient THz radiation in collisional plasma.
- To investigate the role of an external periodic electric field in enhancing THz emission.
Main Methods:
- Utilizing an external periodic electric field in a density-rippled collisional plasma.
- Analyzing the generation of an additional transverse current component.
- Introducing the concept of external field induced THz (EFIT) radiation.
Main Results:
- The external field induces THz radiation (EFIT) by coupling laser and external fields.
- A transverse current component is generated, contributing to THz emission.
- The periodic wave number of the external field allows tuning of THz radiation.
Conclusions:
- An external periodic electric field can overcome adverse collisional effects for efficient THz radiation.
- Tunable resonance conditions are achievable for exciting large amplitude nonlinear plasma currents.
- The EFIT mechanism offers a promising approach for controlled THz generation in collisional plasmas.
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