| A terahertz time-domain spectroscopy system was constructed and characterised in the Ultrafast Spectroscopy Laboratory. This system was then used as a probe beam for pump-probe experiments to help elucidate physics of carrier dynamics in silicon-on-sapphire systems. Specifically, ion-implanted silicon thin films on sapphire substrates and an amorphous silicon thin film on sapphire were investigated. Results from these studies point to the presence of a single carrier relaxation channel in silicon thin film systems. Preliminary 400 nm pump-THz probe experiments have also been performed on silicon nanocrystals in a sapphire substrate. Using a digital filter to mimic convolution issues with the data, a new analysis technique has been shown viable for use in this relatively new laboratory group. Furthermore, the terahertz system is now ready for use not only as a probe beam in a pump-probe experimental configuration, but has also been shown to be a useful far-infrared linear spectroscopy source. |
