Published online by Cambridge University Press: 17 March 2011
The dynamics of the photogenerated carriers in porous silicon and TiO2 anatase was studied at 35 GHz by measuring the change in time of the conductivity s and dielectric constanter. Localization of carriers leads to a positive change ofer, while quasifree carriers to a negative change. Size reduction in Si shortens the recombination time as long as the surface traps are not significant. Magnetic field investigations show opposite variation of conductivity in poroussilicon compared with TiO2.