Studies Organic Ultrathin Film Second-order Nonlinear Optical Properties Of Femto-second Spectrum

People are sharing the convenience which was brought by photocond -ucting device, at she same time, they are requiring smaller faster device for future living. Then, molecular device was attended, and photonics may replace electronics.To get the second-order nonlinear susceptibility and refractive index of films more fastly and simply, we have designed one method which make use of broad band femto-second pulse for measuring the two parameters (named second harmonic femto-second spectrum method). In preterit method, The two parameters must be measured on detached set-up:χ(2) was measured by Make Fringe method; refractive index was deduced by ellipsometry method. The second harmonic generation that was excited by femto-second pulse was detected by spectrograph & CCD, the second harmonic spectrum's intensity as a function of the incident angle of fundamental beam was detected for Second-order nonlinear susceptibility. The movement of spectrum peaks was observed for refractive index. The method was checked by classical method: second-order nonlinear susceptibility was measured by make fringe method; the refractive index was measure by ellipsometry method. In conclusion, the parameters that relate to nonlinear optics properties of films could be measured by the same device. ZrO₂/PAC-azoBNS/PDDA*n is one kind of films, which was assembled by layer-by-layer technique. Its high nonlinear optics properties was proved by second harmonic method, and the values of econd-order nonlinear susceptibility of ZrO₂/PAC-azoBN29%/PDDA is more two hundred twenty times than quartz The second harmonic intensity as linear function of the layers was detected when the fundamental beam's incident angle equal to forty-five degree.