Ultrabroadband Infrared Pump-Probe Spectroscopy Using Chirped-Pulse Upconversion

Abstract

We have demonstrated infrared pump-probe spectroscopy using chirped-pulse upconversion with a nonlinear mixing in a gas. The ultrabroadband mid-infrared spectrum spanning from 200 to 5,000 cm(-1) was upconverted by using a 0.4 ps chirped pulse to visible wavelength generation in gas. This technique allow for the high speed and high sensitivity detection in ultrabroadband mid-infrared region. Ultrafast dynamics of free-carrier in Ge was clearly observed in the range 200-5,000 cm(-1).