title: Amplitude concentration in a phase-modulated spectrum due to femtosecond filamentation.
abstract: We present a method by which the spectral intensity of an ultrafast laser pulse can be accumulated at selected frequencies by a controllable amount. Using a 4-f pulse shaper we modulate the phase of the frequency components of a femtosecond laser. By inducing femtosecond filamentation with the modulated pulse, we can concentrate the spectral amplitude of the pulse at various frequencies. The phase mask applied by the pulse shaper determines the frequencies for which accumulation occurs, as well as the intensity of the spectral concentration. This technique provides a way to obtain pulses with adjustable amplitude using only phase modulation and the nonlinear response of a medium. This provides a means whereby information which is encoded into spectral phase jumps may be decoded into measurable spectral intensity spikes.
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.
authors.forename: J V
authors.initials: JV
authors.lastname: Thompson
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Zhokhov
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Springer
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Traverso
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.
authors.forename: V V
authors.initials: VV
authors.lastname: Yakovlev
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.|M.V. Lomonosov Moscow State University, Physics Department, International Laser Center, 119992 Moscow, Russia.
authors.forename: A M
authors.initials: AM
authors.lastname: Zheltikov
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.|Baylor University, Waco, TX, 76798, USA.
authors.forename: A V
authors.initials: AV
authors.lastname: Sokolov
authors.affiliation: Texas A&M University, College Station, TX, 77843, USA.|Baylor University, Waco, TX, 76798, USA.
authors.forename: M O
authors.initials: MO
authors.lastname: Scully