Open AccessSpectrum broadening of ultrashort ultraviolet pulse in dual-color laser field
Author(s) -
Hong Wang,
Yanling Wang,
Liang’en Ding
Publication year - 2010
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.59.3973
Subject(s) - ultrashort pulse , ultraviolet , laser , optics , materials science , argon , sapphire , protein filament , pulse width modulation , atomic physics , physics , quantum mechanics , voltage , composite material
When collinear dual-color intense laser pulses are overlapped in time, a strong coupling interaction occurs between their plasma filaments. Due to the cross phase modulation, strong non-linear effects are generated and the spectrum width of the ultrafast ultraviolet (UV) pulse is further broadened. The original UV pulse with a bandwidth of 15 nm and energy of 045 mJ is obtained by tripling the frequency of a Ti:sapphire laser system. The UV pulse and the near inferred pulse of 71 mJ can induce plasma filaments separately after focusing within an argon gas cell, leading to an obvious modulation of the UV spectrum. The full width at half maximum of UV spectrum increases to 64 nm which is 4 times the width of spectrum before focusing and 25 times the width of single ultraviolet filament broadening. In this experiment, we mainly study the frequency spectrum evolution of dual-color co-filament in argon gas under the condition of different time delays, coupling locations and gas pressures. Optimizing these factors can yield a valid approach to achieving extremely ultrafast pulses in the range of ultraviolet.