| The advent of synchronously pumped, modelocked, cavity dumped dye lasers and fast photomultipliers has allowed time-resolved photoluminescence spectroscopy to be pushed into the sub-nanosecond and picosecond regime. This enables the transient study of exciton phenomena in semiconductors whose interactions, particularly in direct gap materials, take place on this time scale. Time-resolved spectroscopy allows the direct measurement of transition oscillator strengths, a quantity which is sensitive to theoretical exciton models, thus allowing experimental tests of theory. Time-resolved photoluminescence is also useful for identifying third particle replicas of principle transitions thus enabling estimates of the exciton binding energies to be made. In Si, the lifetimes of the deepest simple acceptors In and T... |
