Backward supercontinuum emission from a filament generated by ultrashort laser pulses in air.
Backward emission of the supercontinuum from a light filament induced by high-intensity femtosecond laser pulses propagating in air has been observed to be enhanced compared with linear Rayleigh-Mie scattering. This enhancement is interpreted as a nonlinear scattering process onto longitudinal refractive-index changes induced by the laser pulse itself. The spectral dependence of the supercontinuum angular distribution is also investigated.
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J
Yu
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D
Mondelain
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G
Ange
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R
Volk
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S
Niedermeier
J P
JP
Wolf
J
J
Kasparian
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R
Sauerbrey