Optical fingerprinting of electron dynamics in wide-bandgap materials

When an electron is excited across the bandgap of a wide-bandgap material, its large, acquired energy can initiate a complex, multi-pathway relaxation back towards the ground state involving, e.g., photon emission, lattice distortion, and electron trapping in meta-stable states. Each electron pathway can give rise to distinct features, i.e. fingerprints, in optical, laser-based measurements, and the project seeks to establish an ultra-broadband and ultra-fast measurement technique that can simultaneously track the temporal evolution of each pathway. Calculations, based on density-functional-theory, will allow for a correct understanding of the atomic-scale nature of the relaxation pathways involved. In combination, these techniques have the potential to significantly advance our fundamental knowledge of the behavior of excited, wide-bandgap materials, which also includes the potential to optimize their technological use within, e.g., radiation dosimetry and radiation detection.