Kinetic Monte Carlo Studies of Spatial Organization in Quantum Dot Self-assembly

Dr. Da Gao
Idaho National Laboratory

In contrast to classical metropolis Monte Carlo method that is good at obtaining equilibrium properties of thermodynamic systems, Kinetic Monte Carlo (KMC) method has been developed to study dynamical phenomena such as surface morphology dynamics and crystal growth. In this talk, I will demonstrate how we have successfully applied KMC to simulate an experimentally observed complex surface morphology with unique features on the (001) surfaces of natural graphite crystals from Namibia. Our KMC studies not only reproduced the experimental results but also well explained why such phenomena happen. Furthermore, based on our KMC simulation results, we proposed a mechanism to control the spatial organization in Quantum Dot Self-assembly: the regular arrangement of steps from a screw dislocation-generated growth spiral provides the overall template for the spatial ordering of quantum dots. An ordered array of quantum dots may be formed or nucleated from impurities driven to the step corners by diffusion and by their interactions with the spiral’s steps and kinks.