@article {ISI:000269815400022, title = {Cross-correlation frequency-resolved optical gating for mid-infrared femtosecond laser pulses by an AgGaGeS4 crystal}, journal = {OPTICS LETTERS}, volume = {34}, number = {16}, year = {2009}, month = {AUG 15}, pages = {2447-2449}, abstract = {We introduce an AgGaGeS4 crystal for sum-frequency generation in cross-correlation frequency-resolved optical gating (XFROG) to characterize mid-IR femtosecond laser pulses between the wavelengths of 3 mu m and 11 mu m. The performance of the AgGaGeS4 crystal was examined by comparing it with a LiNbO3 crystal, which has been frequently used in the near- to mid-IR region. We can obtain XFROG images by the AgGaGeS4 crystal with efficiency 30 times greater than LiNbO3 at the wavelength of 5 mu m. (C) 2009 Optical Society of America}, issn = {0146-9592}, author = {Tsubouchi, Masaaki and Momose, Takamasa} }