Ultrafast time resolved studies of photophysical pathways in OLED materials

The theme of the PhD will be to investigate triplet states and their dynamics in ordered arrays of organic molecules. This will range from new non-excitonic crystals having no coulombic interactions between molecules, to crystals of pure organic molecules consisting of C and H or C, N and H only, which have high intersystem crossing through twisted molecular geometry and non-interacting ground and excited states. J and H aggregates of these molecules will also be investigated as a potential route to very high oscillator strength dopants in hyperfluorescent OLEDs for next generation organic lasers. The student will use a range of time resolved ultrafast laser based spectroscopy techniques to measure the excited state properties of these materials and help to develop a new method for measuring low energy triplet triplet transitions to determine triplet state dependent intersystem crossing and reverse intersystem crossing. They will also gain experience in fabricating state of the art OLED devices and testing them.