Intense broadband THz generation from femtosecond laser filamentation

Abstract

Broadband and energetic terahertz (THz) pulses can be remotely generated in air throughfilamentation. We review such THz generation and detection in femtosecond Ti-sapphire laser inducedremote filaments. New results are presented on the direct relationship between THz generation in atwo color filament and induced N2 fluorescence through population trapping during molecularalignment and revival in air. This further supports the new technique of remote THz detection in airthrough the sensitive measurement of N2 fluorescence.