| Publication Type |
dissertation |
| School or College |
College of Mines & Earth Sciences |
| Department |
Materials Science & Engineering |
| Author |
Ming, Wenmei |
| Title |
Atomistic simulation of charge effects: from tunable thin film growth to isolation of surface states with spin-orbit coupling |
| Date |
2015 |
| Description |
This dissertation revitalizes the importance of surface charge effects in semiconductor nanostructures, in particular in the context of thin film growth and exotic electronic structures under delicate spin-orbit coupling. A combination of simulation techniques, including density functional theory calculation, kinetic Monte Carlo method, nonequilibrium Green's function method, and tight binding method, were employed to reveal the underlying physical mechanisms of four topics: (1) Effects of Li doping on H-diffusion in MgH2 for hydrogen storage. It addresses both the effect of Fermi level tuning by charged dopant and the effect of dopant-defect interaction, and the latter was largely neglected in previous works; (2) Tuning nucleation density of the metal island with charge doping of the graphene substrate. It is the first time that the surface charge doping effect is proposed and studied as an effective approach to tune the kinetics of island nucleation at the early stage of thin film growth; (3) Complete isolation of Rashba surface states on the saturated semiconductor surface. It shows that the naturally saturated semiconductor surface of InSe(0001) with Au single layer film provides a mechanism for the formation of Rashba states with large spin splitting; it opens up an innovative route to obtaining ideal Rashba states without the overwhelming bulk spin-degenerate carriers in spin-dependent transport; (4) Formation of large band gap quantum spin Hall state on Si surface. This study reveals the importance of atomic orbital composition in the formation of a topological insulator, and shows promisingly the possible integration of topological insulator technology into Si-based modern electronic devices. |
| Type |
Text |
| Publisher |
University of Utah |
| Subject |
diffusion and defect; Grapene; Rashba states; spin transport; substrate charge doping; topological insulator |
| Dissertation Name |
Doctor of Philosophy |
| Language |
eng |
| Rights Management |
Copyright © Wenmei Ming 2015 |
| Format Medium |
application/pdf |
| Format Extent |
27,276 bytes |
| Identifier |
etd3/id/3836 |
| ARK |
ark:/87278/s6b02d5k |
| Setname |
ir_etd |
| ID |
197387 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6b02d5k |
