title: Optical pulse compression to 3.4 fs in the monocycle region by feedback phase compensation.
abstract: We compensated for chirp of optical pulses with an over-one-octave bandwidth (495-1090 nm; center wavelength of 655.4 nm) produced by self-phase modulation in a single argon-filled hollow fiber and generated 3.4-fs, 1.56 optical-cycle pulses (500 nJ, 1-kHz repetition rate). This was achieved with a feedback system combined with only one 4-f phase compensator with a spatial light modulator and a significantly improved phase characterizer based on modified spectral phase interferometry for direct electric-field reconstruction. To the best of our knowledge, this is the shortest pulse in the visible-to-infrared region.
authors.affiliation: Department of Applied Physics, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo 060-8628, Japan. k-yamane@eng.hokudai.ac.jp
authors.forename: Keisaku
authors.initials: K
authors.lastname: Yamane
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Oka
authors.forename: Ryuji
authors.initials: R
authors.lastname: Morita
authors.forename: Mikio
authors.initials: M
authors.lastname: Yamashita
authors.forename: Akira
authors.initials: A
authors.lastname: Suguro