Dynamic studies of degenerate four-wave-mixing in an azobenzene-doped polymer film with an optical pump

Degenerate four-wave-mixing was performed in azobenzene-doped polymethyl methacrylate film under a low power continuous-wave laser at 632.8 nm with a pulsed pump laser of 532 nm. Different temporal profiles of the degenerate four-wave-mixing signal were observed under different pump energies, which originated from the relaxation processes between the energy levels of azobenzene during the photoisomerization, especially the transferring processes between the triplet states of the two isomers, trans and cis.