We build a frequency resolved optical gating (FROG) setup based on the second harmonic generation (SHG) FROG to characterize the mid-infrared (MIR) few-cycle laser pulse in single shot basis. Considering the extremely wide bandwidth, we use 20-µm-thick BBO crystal as the nonlinear medium, and correct the spectral response with the frequency summing efficiency. Spatial splitting is adopted to avoid additional material dispersion. In combination with a 4f imaging, this configuration enables the setup to run in single shot. With the central wavelength of 1.8 µm, the measured pulse has a duration of 9.3 fs, which corresponds to about 1.5 cycles.
© 2012 Chinese Optics Letters
(140.7090) Lasers and laser optics : Ultrafast lasers
(320.7090) Ultrafast optics : Ultrafast lasers
(320.7100) Ultrafast optics : Ultrafast measurements
(320.7160) Ultrafast optics : Ultrafast technology
Canhua Xu, Chuang Li, Liwei Song, Ding Wang, and Yuxin Leng, "Few-cycle mid-infrared pulse full characterization in single shot," Chin. Opt. Lett. 10, 123202-123202 (2012)