“Charge and Spin Transport in Disordered Graphene-Based Materials” is Thesis defended in 2014 by Dr. Dinh Van Tuan, former member of the Theoretical and Computational Nanoscience Group. It has now been awarded and published in Springer Theses, a series for "Recognizing Outstanding Ph.D. Research".
The PhD Thesis defended in 2014 by Dr. Dinh Van Tuan, former member of the Theoretical and Computational Nanoscience Group led by ICREA Prof Stephan Roche, has been published in Springer Theses, where outstanding theses from internationally top-ranked research institutes are nominated. The awarded research work, entitled “Charge and Spin Transport in Disordered Graphene-Based Materials”, presents an in-depth theoretical analysis of charge and spin transport properties in complex forms of disordered graphene.
The Thesis relies on innovative real space computational methods of the time-dependent spreading of electronic wave packets. First a universal scaling law of the elastic mean free path versus the average grain size is predicted for polycrystalline morphologies, and charge mobilities of up to 300.000 cm2/V.s are determined for 1 micron grain size, while amorphous graphene membranes are shown to behave as Anderson insulators. An unprecedented spin relaxation mechanism, unique to graphene and driven by spin/pseudospin entanglement, is then reported in the presence of weak spin-orbit interaction together with the prediction of a crossover from a quantum spin Hall Effect to spin Hall effect, depending on the degree of surface ad-atom segregation and the resulting island diameter.