Abstract
Ultrafast laser spectroscopy is an efficient tool of investigation of charge carrier dynamics in semiconductors. We describe the principles of techniques of femtosecond laser spectroscopy as applied for study of photoexcited carrier dynamics in sub-band-gap energy states in nanocrystalline diamond self-supporting membranes prepared by plasma-enhanced chemical vapor deposition method.
Our results of the femtosecond transient transmission and photoluminescence laser spectroscopy indicate relaxation of photoexcited carriers with the time constants of the order of 1 ps. This is attributed to an ultrafast spatial separation of holes and electrons at the surface of nanocrystals.
We reported also on the nonlinear optical properties of nanocrystalline membranes.