Enhancing SLKMC Simulation with a User-Friendly GUI: Overview and Future Directions

1. A Graphical User Interface for the SLKMC Simulator - Charlie Thornton -

2. Overview • Background • SLKMC: What it is and how it works • Problem Description and Analysis • The User Interface • Demonstration • Validation • Future Work

3. The Big Picture Simulator Input(Text Files) KMC Simulator(FORTRAN) Simulator Output(Text Files)

4. Background: Modeling Atoms • Simulate the growth of substances on a substrate • KMC simulations model the movements of individual atoms

5. Self-Learning Kinetic Monte-Carlo (SLKMC) • Every MC step, at least one atom moves • Different MC steps represent different amounts of time Experimental SLKMC validation – Coalescence

6. SLKMC: Configurations • We simulate the motion of active atoms • All active atoms have a configuration • 36 surrounding atoms • Atoms outside the configuration can be ignored • This makes concurrent simulations possible

7. SLKMC: Processes (Transitions) 0.110 eV 0.389 eV 0.433 eV

8. The Simulation • For some number of MC steps, do the following: • Select a process to perform (weighted-random, based on energy threshold) • Select an active atom at which we can perform that process • Apply the process at that active atom • Update process information for any affected atoms

9. Simulation Analysis • Playback of the Simulation Movie • Provides an intuitive understanding of simulation flow • Helps to identify important moments in the simulation • Process Statistics • Identifies important processes • Island Motion • Track the center of mass of islands of atoms

10. Input and Output • Input Files: • Main Configuration File • Simulation Database • Substrate Configuration File • Initial Mesh Configuration • Results • Updated Database • Simulation Movie (Snapshots) • Process History (“trace” or “stack”) • Process Statistics

11. The User Interface • KMC-Vis Provide a single interface to help users: • Edit simulation input files • Run the simulation • Analyze results data • KMC-Mesh • Focused on initial mesh configuration • Can be launched from within KMC-Vis

12. Demonstration • Since KMC-Vis is a Java Web Start application, it can be launched from the web:http://www.cis.ksu.edu/~clt3955/research.php

13. Validation • User Reviews • Two SLKMC developers / users evaluated the software • 3D visualization • Crystal structure generation • Symmetry detection • Saves time • Many ideas for additional features

14. Future Work • Pre-processing • Create new input files (rather than modifying existing ones) • Process database editor • Extend KMC-Mesh to support substrate configuration files • Simulator Interaction • Provide a mechanism to run and track a simulation from within the software

15. Future Work • Data Analysis • Center of mass tracking data • Symmetry data persistence • Allow user to constrain the scope of results data to include only important time windows • Miscellaneous • Draw results data from new process history file • Support new 210 neighbor shell model