Phase matching and the spectrum of high-order harmonics generated in an extended medium

Journal Article · Fri Mar 31 00:00:00 EST 2000 · Quantum Electronics (Woodbury, N.Y.)

DOI:https://doi.org/10.1070/QE2000V030N03ABEH001694· OSTI ID:21454662

Platonenko, Viktor T; Strelkov, V V ^[1]

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1. Department of Physics, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

We present analytical and numerical calculations of the power and angular distributions of high-order harmonics generated by limited laser beams in extended media with a dispersion weak when compared with the geometric dispersion. When the thickness of the harmonic-generating layer is large, the spectrum of high-order harmonics differs considerably from the spectrum of a single-atom response. In particular, two plateaus may arise in the spectrum of high-order harmonics owing to the off-axially phase-matched generation of certain harmonics (the generation of a part of the angular spectrum of these harmonics is phase-matched). The efficient off-axially phase-matched harmonic generation is provided mainly by amplitude modulation of the high-frequency response of a medium to the pump field in the cross section of the beam, which broadens the radiation pattern of harmonic emission. Off-axially phase-matched harmonic generation in Gaussian beams is possible with any geometric dispersion (with an arbitrarily tight focusing). The results of our calculations agree well with the experimental data on high-order harmonic generation in thick gas layers available from the literature. (nonlinear optical phenomena and devices)

• OSTI ID: 21454662
• Journal Information: Quantum Electronics (Woodbury, N.Y.), Vol. 30, Issue 3; Other Information: DOI: 10.1070/QE2000v030n03ABEH001694; ISSN 1063-7818
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLITUDES
ANALYTICAL SOLUTION
ANGULAR DISTRIBUTION
ATOMS
DISPERSIONS
EMISSION
EXPERIMENTAL DATA
FREQUENCY MODULATION
GEOMETRY
HARMONIC GENERATION
LASERS
LAYERS
NUMERICAL SOLUTION
PHOTON BEAMS
POWER DISTRIBUTION
SPECTRA
BEAMS
DATA
DISTRIBUTION
FREQUENCY MIXING
INFORMATION
MATHEMATICAL SOLUTIONS
MATHEMATICS
MODULATION
NUMERICAL DATA