nondegenerate pump-probe spectroscopy

Kerr and free carrier ultrafast all-optical switching of GaAs/AlAs nanostructures near the three photon edge of GaAs
A. Hartsuiker, P. J. Harding, Y. R. Nowicki-Bringuier, J. Gérard, and W. L. Vos
J. Appl. Phys. 104, 083105: 1-7 (2008)