Date of Award
Doctor of Philosophy (PhD)
Nuclear magnetic resonance (NMR) has shown its ability to be a very informative analytical technique due to the ability to measure very small changes in the energy splittings due to the nuclei’s local environment. However, this ability is hindered by the low sensitivity of the experiment. Many methods have been postulated and implemented to enhance the sensitivity of NMR experiments; one of which is optically pumped NMR (OPNMR). In this dissertation, the usefulness and potential applications of OPNMR are presented. First, a doubly resonant OPNMR probe was fabricated in order to complete more advanced NMR techniques while optically pumping the semiconductor sample. OPNMR was then shown to be very beneficial and accurate for measuring light hole transitions in semiconductors, which are typically difficult to observe using traditional techniques. The optical pumping behavior of a sample (CdTe) has been debated, but was measured here in order to obtain the expected trends and behavior. Discussion of the potential uses of optically oriented isolated spins pairs is presented and the characterization of such spin pairs is implemented, which included the first experimental report of a postulated NMR sequence (a version of spin echo double resonance). An Al2O3/GaAs interface was studied by OPNMR in order to observe the properties for the first time and the measured polarization was much higher than previously reported. Lastly, molecular dynamic and density functional theory calculations were used collaboratively to provide an accurate model for amorphous alumina.
Chair and Committee
Sophia E. Hayes
Parag Banerjee, Alexander Barnes, Bryce Sadtler, Jacob Schaefer,
Willmering, Matthew M., "Nuclear Spin Alignment in Optically Pumped Semiconductors" (2017). Arts & Sciences Electronic Theses and Dissertations. 1156.