Date of Award
8-2014
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Legacy Department
Physics
Committee Chair/Advisor
Dr. Murray S. Daw
Committee Member
Dr. Bradley Meyer
Committee Member
Dr. Catalina Marinescu
Committee Member
Dr. Sumanta Tewari
Abstract
A new method (second moment approximation method) of calculating mode lifetimes of materials has been proposed by Dickel and Daw [14, 15]. The method was tested on an anharmonic lattice model, and it shows consistency with results from using traditional method (molecular dy-namics with Green-Kubo [2]) at high temperatures, but deviates at low temperatures. Based on this method, we developed the fourth moment approximation method, and tested it on various models from 1D anharmonic chain to the FCC cube with Lennard-Jones potential. Calculations showed that the fourth moment approximation method provides a fast and reliable scheme to calculate mode lifetimes at wide range of temperatures, and this scheme can be used on many different materials.
Recommended Citation
Gao, Yang, "Fourth Moment Approximation of Instrinsic Mode Lifetimes in Solids" (2014). All Dissertations. 1468.
https://open.clemson.edu/all_dissertations/1468