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Apparent superluminal propagation of a laser pulse in a dispersive medium
P Sprangle1, J R Peñano, B Hafizi
1Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375, USA.
Abstract:
The distortion of a laser pulse propagating in a dispersive gain/absorptive medium is analyzed. The relationship between the distortion of the pulse and superluminal propagation is discussed. We present an analytical approach based on the laser envelope equation that is readily applicable to arbitrary input pulse shapes. This analysis is used to interpret recent experiments that claim to have observed distortionless superluminal laser pulse propagation.
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