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Title: Highly focused and efficient terahertz radiation generation by photo-mixing of lasers in plasma in the presence of magnetic field

Abstract

A mechanism of efficient and highly focused terahertz (THz) radiation generation by photo-mixing of top-hat like lasers with frequencies ω{sub 1}, ω{sub 2} and wave numbers k{sub 1}, k{sub 2} in pre-formed rippled density (corrugated) plasma is proposed. In this mechanism, intensity variation of lasers offers nonlinear ponderomotive force at frequency ω{sup ′}=ω{sub 1}−ω{sub 2} and wave number k{sup ′}=k{sub 1}−k{sub 2} which couples with density ripples in the plasma and leads to a strong nonlinear oscillatory current that resonantly excites highly focused and intense THz radiation at frequency ω{sub UH}=√((ω{sub p}{sup 2}+ω{sub c}{sup 2})) (where ω{sub c} is electron cyclotron frequency). The efficiency of emitted THz radiation of the order of 15% is obtained under optimum conditions. It is observed that focus and intensity of emitted radiation can be controlled by selecting a proper profile index of the lasers, ripple parameters, and tuning of external magnetic field.

Authors:
 [1];  [2];  [3]
  1. Department of Physics, Multani Mal Modi College Modinagar, C.C.S. University, Meerut, Uttar Pradesh 201204 (India)
  2. Singh Simutech Pvt. Ltd., Bharatpur, Rajasthan 321201 (India)
  3. Jaypee Institute of Information Technology, Noida 201307 (India)
Publication Date:
OSTI Identifier:
22299844
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CURRENTS; CYCLOTRON FREQUENCY; EMISSION; LASERS; MAGNETIC FIELDS; NONLINEAR PROBLEMS; PLASMA; PONDEROMOTIVE FORCE

Citation Formats

Malik, Anil K., E-mail: anilkmalik@gmail.com, Singh, Kunwar Pal, and Sajal, V. Highly focused and efficient terahertz radiation generation by photo-mixing of lasers in plasma in the presence of magnetic field. United States: N. p., 2014. Web. doi:10.1063/1.4890852.
Malik, Anil K., E-mail: anilkmalik@gmail.com, Singh, Kunwar Pal, & Sajal, V. Highly focused and efficient terahertz radiation generation by photo-mixing of lasers in plasma in the presence of magnetic field. United States. doi:10.1063/1.4890852.
Malik, Anil K., E-mail: anilkmalik@gmail.com, Singh, Kunwar Pal, and Sajal, V. 2014. "Highly focused and efficient terahertz radiation generation by photo-mixing of lasers in plasma in the presence of magnetic field". United States. doi:10.1063/1.4890852.
@article{osti_22299844,
title = {Highly focused and efficient terahertz radiation generation by photo-mixing of lasers in plasma in the presence of magnetic field},
author = {Malik, Anil K., E-mail: anilkmalik@gmail.com and Singh, Kunwar Pal and Sajal, V.},
abstractNote = {A mechanism of efficient and highly focused terahertz (THz) radiation generation by photo-mixing of top-hat like lasers with frequencies ω{sub 1}, ω{sub 2} and wave numbers k{sub 1}, k{sub 2} in pre-formed rippled density (corrugated) plasma is proposed. In this mechanism, intensity variation of lasers offers nonlinear ponderomotive force at frequency ω{sup ′}=ω{sub 1}−ω{sub 2} and wave number k{sup ′}=k{sub 1}−k{sub 2} which couples with density ripples in the plasma and leads to a strong nonlinear oscillatory current that resonantly excites highly focused and intense THz radiation at frequency ω{sub UH}=√((ω{sub p}{sup 2}+ω{sub c}{sup 2})) (where ω{sub c} is electron cyclotron frequency). The efficiency of emitted THz radiation of the order of 15% is obtained under optimum conditions. It is observed that focus and intensity of emitted radiation can be controlled by selecting a proper profile index of the lasers, ripple parameters, and tuning of external magnetic field.},
doi = {10.1063/1.4890852},
journal = {Physics of Plasmas},
number = 7,
volume = 21,
place = {United States},
year = 2014,
month = 7
}
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