title: Frequency-resolved optical gating system with a tellurium crystal for characterizing free-electron lasers in the wavelength range of 10-30 microm.
abstract: A second-harmonic generation frequency-resolved optical gating (SHG-FROG) system has been developed for the complete characterization of laser pulses in the wavelength range of 10-30 microm. A tellurium crystal is used so that spectrally resolved autocorrelation signals with a good signal-to-noise ratio are obtained. Pulses (wavelength approximately 22 microm) generated from a free-electron laser are measured by the SHG-FROG system. The SHG intensity profile and the spectrum obtained by FROG measurements are well consistent with those of independent measurements of the pulse length and spectrum. The pulse duration and spectral width determined from the FROG trace are 0.6 ps and 5.2 THz at full width half maximum, respectively.
authors.affiliation: Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan. hokuto@hiroshima-u.ac.jp
authors.forename: Hokuto
authors.initials: H
authors.lastname: Iijima
authors.forename: Ryoji
authors.initials: R
authors.lastname: Nagai
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Nishimori
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Hajima
authors.forename: Eisuke J
authors.initials: EJ
authors.lastname: Minehara