Cheng-Wei Lee, Ph.D. Materials Science
Member: Fall 2014 to Fall 2019
Dissertation Title: Non-adiabatic electron-ion dynamics in semiconductors under ionizing particle irradiation
Contact information: clee152@illinois.edu
Research Interest: I have general interests in electronic and optical properties of solids, especially of semiconductors. I have been studying on non-adiabatic electron-ion dynamics via real-time time-dependent density functional theory (RT-TDDFT). Non-adiabatic effect is neglected in the current first-principles molecular dynamics simulations, which assume Born-Oppenheimer (BO) approximation. However, BO approximation breaks down when a fast-varying potential exists in the system. For example, when a high-energy ion bombards the target materials, e.g. ion-implantation process in semiconductor industry, the system is exposed to a fast-varying potential resulting from the fast-moving ion. Inelastic collision events are known to dominate and are characterized by electronic stopping power. It has been demonstrated that such phenomena cannot be captured by first-principles molecular dynamics and time-dependent quantum mechanical treatments such as TDDFT are required. In short, this computational approach will lead us to better understandings of how ion radiations interact with materials, which are essential to address stability issues of semiconductor device under radiation and spatial-control issues for focused-ion-beam related process.
Journal Articles
2023
Accelerating Electronic Stopping Power Predictions by 10 Million Times with a Combination of Time-Dependent Density Functional Theory and Machine Learning Journal Article Forthcoming
In: Forthcoming.
Identifying native point defect configurations in α-alumina Journal Article
In: J. Phys.: Condens. Matter, vol. 35, pp. 334002, 2023.
2022
Electron dynamics in extended systems within real-time time-dependent density functional theory Journal Article
In: MRS Communications, vol. 12, pp. 1002-1014, 2022.
2021
Real-Time Exciton Dynamics with Time-Dependent Density-Functional Theory Journal Article
In: Phys. Rev. Lett., vol. 127, pp. 077401, 2021.
2020
Multiscale simulations of electron and ion dynamics in self-irradiated silicon Journal Article
In: Phys. Rev. B, vol. 102, pp. 024107, 2020.
2019
Hot-Electron-Mediated Ion Diffusion in Semiconductors for Ion-Beam Nanostructuring Journal Article
In: Nano Lett., vol. 19, pp. 3939-3947, 2019.
Solid-State Divalent Ion Conduction in ZnPS$_3$ Journal Article
In: Chem. Mater., vol. 31, pp. 3652-3661, 2019.
Pushing the frontiers of modeling excited electronic states and dynamics to accelerate materials engineering and design Journal Article
In: Comput. Mater. Sci., vol. 160, pp. 207-216, 2019.
2018
Electronic stopping and proton dynamics in InP, GaP, and In0.5Ga0.5P from first principles Journal Article
In: Eur. Phys. J. B, vol. 91, pp. 222, 2018.
Novel diffusion mechanism in the presence of excited electrons?: Ultrafast electron--ion dynamics in proton-irradiated magnesium oxide Journal Article
In: Mater. Today, vol. 21, pp. 925-927, 2018.
Conferences
2019
Impact of Computational Curricular Reform on Non-participating Undergraduate Courses: Student and Faculty Perspective Conference
2019 ASEE Annual Conference & Exposition, American Society for Engineering Education 2019.