Ultrafast transient absorption spectrometer

The spectrometer is highly versatile and flexible and can be easily configured for different optical techniques. In general, in transient absorption experiments the pump pulse interacts with the system of interest, after which the transient absorption change in the sample is monitored by a time-delayed probe beam. The transient absorption spectrum contains clues to both structural information and dynamics. The TAS device can operate in two spectral regimes covering probe wavelengths from 400 nm to 800 nm or 800 nm to 1600 nm. The optical delay line provides femtosecond temporal resolution over a range as wide as 3.2 ns.
The direct output of the OPA’s can also be coupled into the spectrometer, thus extending the operation spectral range all the way to MIR region.
There is a potential to conduct time-resolved femtosecond Stimulated Raman scattering (SRS) experiments using the exsistent setup. SRS is a nonlinear optical technique that is sensitive to molecular bond vibrations. This configuration potentially allows broadband SRS experiments, with a spectral resolution defined by the spectral width of the pump beam. We will insert narrow bandpass filter into pump beam to provide a resolution of 25 cm-1 or better.

Useful reading:

Application note (Newport Corp) pdf