Broadband mid-infrared phase retrieval for nonlinear microscopy

Abstract

Spectral phase characterization of ultrashort laser pulses is essential in nonlinear micro-spectroscopy. Whereas in many applications phases are determined for near-infrared (NIR) pulses, successful mid-infrared (MIR) phase retrieval is rare. The spectral phase of ultra-broadband MIR pulses is determined over more than 1000 c m − 1 in the presented work. This is accomplished by exploiting the d-scan method in two variants. Both allow for detecting high signals by using the interaction of the MIR and NIR pulses. The two variants differ in imprinting the dispersion. While the dual d-scan imprints phases on both pulses, the Xd-scan method disperses the NIR pulses solely.