Frequency-resolved optical gating system with a tellurium crystal for characterizing free-electron lasers in the wavelength range of 10-30 microm

Hokuto Iijima; Ryoji Nagai; Nobuyuki Nishimori; Ryoichi Hajima; Eisuke J Minehara

doi:10.1063/1.3265318

Frequency-resolved optical gating system with a tellurium crystal for characterizing free-electron lasers in the wavelength range of 10-30 microm

Rev Sci Instrum. 2009 Dec;80(12):123106. doi: 10.1063/1.3265318.

Authors

Hokuto Iijima¹, Ryoji Nagai, Nobuyuki Nishimori, Ryoichi Hajima, Eisuke J Minehara

Affiliation

¹ Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan. hokuto@hiroshima-u.ac.jp

PMID: 20059130
DOI: 10.1063/1.3265318

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.