Can I perform experiments with ultra-short laser pulses using the GEMINI?

If the GEMINI is placed “after the sample” (i.e. when the light has already interacted with the sample), then it is possible to use it with ultra-short laser pulses, as it does not affect the temporal resolution of your experiment. As an example, you can refer to this application in pump-probe spectroscopy.
Instead, if you need to use the interferometer “before the sample”, then the GEMINI-2D is the most suitable device. As an example, the GEMINI-2D is used in bidimensional electronic spectroscopy (2DES), in which it creates two replicas of ultra-short pump pulses with a precise control on the dispersion.