The Study of the Interaction of Intense Picosecond Light Pulse with Materials (1) Measurement of Picosecond Pulse Width Using Two-Photon Conductivity in GaAs. (2) Three Photon Conductivity in CdS

摘要

Two-photon conductivity effect in GaAs has been used to map the second order intensity correlation function of the picosecond laser pulse for the first time. Reproducible data were obtained. The contrast ratio is about 1.8. This is limited by the thickness of the sample. In principle this method can be extended to use very thin sample to obtained subpicosecond time resolution. Three photon induced photoconductivity effect has been observed in CdS polycrystalline sample with a mode-locked Nd:glass laser. The three photo absorption coefficient was measured to be 0.043 cc/G(W sq). (Author)