The electronic ?(3) nonlinear optical behaviour of blue, thermally evaporated P4BCMU has been investigated at ?=1.064 µm using TM-polarized grating coupled guided-wave techniques. The analysis involves a rigorous treatment of the electromagnetic fields in the vicinity of the grating and a theoretically generated fit to the nonlinear reflectivity response which yields both the real and the imaginary components of ?(3) in a single experiment. The values obtained are Re(?(3))=-(1.3±0.4)x10-10 esu and Im(?(3))=(2.1±0.6) x 10-10 esu. Considerable care has been taken to establish the electronic origin of the effect. The results show a significant increase in two-photon absorption relative to red spun films of the same polymer at 1.064 µm. © 1994.
|Number of pages||9|
|Publication status||Published - 15 Dec 1994|