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Title: Powerful terahertz emission from laser wakefields in inhomogeneous magnetized plasmas

Abstract

Powerful coherent terahertz (THz) pulses with a broad spectrum (0.1-3 THz) can be produced from a laser-driven wakefield through linear mode conversion in inhomogeneous magnetized plasmas with the maximum plasma density of 10{sup 17} cm{sup -3}. This occurs when a laser pulse, with an optimized duration about 300 fs, is incident either normally or obliquely to the density gradient of inhomogeneous magnetized plasmas. The external dc magnetic field has a magnitude of a few tesla. By changing the strength and direction of the magnetic field, one can enhance or suppress the THz emission. The maximum energy conversion efficiency in the magnetized plasmas can be double that in the unmagnetized plasmas. Such wakefield emission can be a powerful THz source at the MW level and capable of affording field strength of a few MV/cm, suitable for THz nonlinear physics. Because these THz emissions are always with a positive chirp, with a proper dispersion compression, single-cycle THz pulses can be generated with higher peak powers and field strengths.

Authors:
; ; ;  [1];  [2]
  1. Beijing National Laboratory for Condensed Matters, Institute of Physics, Chinese Academy of Science, Beijing 100080 (China)
  2. Institute of Computer Science, National University of Defence Technology, Changsha 410073 (China)
Publication Date:
OSTI Identifier:
21072283
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevE.75.016407; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPRESSION; ENERGY CONVERSION; LASERS; LIGHT TRANSMISSION; MAGNETIC FIELDS; MAGNETIZATION; MODE CONVERSION; NONLINEAR PROBLEMS; PHOTON EMISSION; PLASMA; PLASMA DENSITY; PLASMA SIMULATION; PULSES; THZ RANGE

Citation Formats

Wu Huichun, Sheng Zhengming, Dong Quanli, Zhang Jie, and Xu Han. Powerful terahertz emission from laser wakefields in inhomogeneous magnetized plasmas. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.016407.
Wu Huichun, Sheng Zhengming, Dong Quanli, Zhang Jie, & Xu Han. Powerful terahertz emission from laser wakefields in inhomogeneous magnetized plasmas. United States. doi:10.1103/PHYSREVE.75.016407.
Wu Huichun, Sheng Zhengming, Dong Quanli, Zhang Jie, and Xu Han. Mon . "Powerful terahertz emission from laser wakefields in inhomogeneous magnetized plasmas". United States. doi:10.1103/PHYSREVE.75.016407.
@article{osti_21072283,
title = {Powerful terahertz emission from laser wakefields in inhomogeneous magnetized plasmas},
author = {Wu Huichun and Sheng Zhengming and Dong Quanli and Zhang Jie and Xu Han},
abstractNote = {Powerful coherent terahertz (THz) pulses with a broad spectrum (0.1-3 THz) can be produced from a laser-driven wakefield through linear mode conversion in inhomogeneous magnetized plasmas with the maximum plasma density of 10{sup 17} cm{sup -3}. This occurs when a laser pulse, with an optimized duration about 300 fs, is incident either normally or obliquely to the density gradient of inhomogeneous magnetized plasmas. The external dc magnetic field has a magnitude of a few tesla. By changing the strength and direction of the magnetic field, one can enhance or suppress the THz emission. The maximum energy conversion efficiency in the magnetized plasmas can be double that in the unmagnetized plasmas. Such wakefield emission can be a powerful THz source at the MW level and capable of affording field strength of a few MV/cm, suitable for THz nonlinear physics. Because these THz emissions are always with a positive chirp, with a proper dispersion compression, single-cycle THz pulses can be generated with higher peak powers and field strengths.},
doi = {10.1103/PHYSREVE.75.016407},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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