title: Terahertz modulation induced by filament interaction.
abstract: We experimentally demonstrated that nonlinear filament interaction could spectrally modulate terahertz (THz) radiation generated from asymmetric two-color filaments. It was the spatial plasma density modulation in plasma channels that induced the THz spectral modulation. As a result of optical manipulation of electron density in the filamentary plasma gratings, the proportion of high-frequency THz spectra increased, while that of low-frequency THz spectra decreased, indicating that the increase of free electron density in the filamentary plasma grating brought about THz frequency upshifts.
authors.forename: Boqu
authors.initials: B
authors.lastname: He
authors.forename: Junyi
authors.initials: J
authors.lastname: Nan
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.forename: Shuai
authors.initials: S
authors.lastname: Yuan
authors.forename: Heping
authors.initials: H
authors.lastname: Zeng