First-principles studies of defect dynamics in crystalline solids
Author
Yoshimura, AnthonyOther Contributors
Meunier, Vincent; Giedt, Joel; Koratkar, Nikhil A.; Terrones, H. (Humberto); Zhang, Shengbai;Date Issued
2020-05Subject
PhysicsDegree
PhD;Terms of Use
This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.; Attribution-NonCommercial-NoDerivs 3.0 United StatesMetadata
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To this end, two classes of defect dynamics are considered. The first is passive dynamics, in which the evolution of defects is probabilistic, and its rate is dictated only by the environmental conditions in which the material exists. For this, thermally induced defect creation and migration in various materials are modeled by employing the nudged elastic band method to determine the energy barriers for these processes, from which the Arrhenius equation is used to relate those barriers to rates of occurrence. The second class is active defect dynamics, in which defects are intentionally produced, guided, and precisely manipulated under properly tuned electron beam irradiation. Here, we lay out how DFT can be combined with quantum electrodynamics to reveal how phononic and electronic excitations affect the atomic displacement rates in response to the incident beam electron collisions. In doing so, we provide theoretical support for the use of the electron beam as a reliable high-precision instrument for atomic-scale defect engineering in various materials. We hope that such an understanding of defect dynamics can grant materials en- gineers the ability to tune and control the properties of novel materials for the purpose of targeted functionality.; Any crystalline material inevitably contains interruptions in its crystal structure, which are called defects. While sometimes detrimental to the material’s performance, these defects drastically expand the space of properties accessible to the crystal, often introducing variations in electronic, vibrational, and optical attributes. It follows that the control and prediction of these defects can vastly extend the range of applications for materials in modern devices. In this work, we use first-principles density functional theory (DFT) to simulate the time evolution of these defects in several crystalline materials and suggest means by which they can be controlled and manipulated.;Description
May 2020; School of ScienceDepartment
Dept. of Physics, Applied Physics, and Astronomy;Publisher
Rensselaer Polytechnic Institute, Troy, NYRelationships
Rensselaer Theses and Dissertations Online Collection;Access
CC BY-NC-ND. Users may download and share copies with attribution in accordance with a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License. No commercial use or derivatives are permitted without the explicit approval of the author.;Collections
Except where otherwise noted, this item's license is described as CC BY-NC-ND. Users may download and share copies with attribution in accordance with a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License. No commercial use or derivatives are permitted without the explicit approval of the author.