Anisotropic effects of terahertz emission from laser sparks in air

Journal Article · Mon Nov 15 04:00:00 EST 2010 · Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print)

DOI:https://doi.org/10.1103/PHYSREVE.82.056409· OSTI ID:21502862

Zharova, N A; Mironov, V A; Fadeev, D A ^[1]

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1. Institute of Applied Physics, Russian Academy of Sciences, 46 Ulianov Street, Nizhny Novgorod 603950 (Russian Federation)

Strong terahertz (THz) radiation can be generated by intense femtosecond laser pulses propagating in air. The excitation of transient current induced in the wake just behind the laser pulse is studied in detail using numerical simulations on the basis of Maxwell's equations for THz-band fields and hydrodynamic model for the plasma motion. It is shown that the thermal effects, anisotropic in character in the case of linear polarized laser field, can explain observed quadrupole-type THz radiation pattern in the experiment performed by Akhmedzhanov et al. [Radiophys. Quantum Electron. 52, 482 (2009)]. Taking into account the transverse structure of the plasma filament, our numerical code enables us to calculate the spatial distribution and temporal evolution of terahertz electron current, its spectrum, and angular emission pattern. It is shown that an expansion of full fields in terms of azimuthal modes is a useful tool for research of THz generation in many situations of practical interest.

• OSTI ID: 21502862
• Journal Information: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print), Journal Name: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print) Journal Issue: 5 Vol. 82; ISSN 1539-3755
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AIR
ANISOTROPY
COMPUTERIZED SIMULATION
DIFFERENTIAL EQUATIONS
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ENERGY-LEVEL TRANSITIONS
EQUATIONS
EVOLUTION
EXCITATION
EXPANSION
FERMIONS
FLUIDS
GASES
HYDRODYNAMIC MODEL
LASER RADIATION
LASERS
LEPTONS
MATHEMATICAL MODELS
MAXWELL EQUATIONS
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE MODELS
PLASMA
PLASMA FILAMENT
PULSES
RADIATIONS
SIMULATION
SPATIAL DISTRIBUTION
STATISTICAL MODELS
THERMODYNAMIC MODEL