15–19 Sept 2019
Orto Botanico - Padova
Europe/Rome timezone

Machine learning for Cu surface kinetic Monte Carlo

19 Sept 2019, 09:10
20m
Orto Botanico - Auditorium

Orto Botanico - Auditorium

Oral Modeling and Simulations Modeling and Simulations - Applications

Speaker

Jyri Kimari

Description

Kinetic Monte Carlo (KMC) is among the most efficient methods for modelling diffusion. In the context of CLIC, we're interested in the diffusion processes on the Cu surface - especially under high electric fields that are present prior to electric breakdown events.

The accuracy of a KMC model relies on the comprehensiveness of the catalogue of different migration events that are available for the simulated system, and on the accuracy of the energy barriers associated with those events. The heavy calculations required to find the energy barriers are typically the bottleneck of KMC simulations.

We are improving the KMC model earlier developed in our group, by adding nuance to the way we describe the atomic environments of the migration events, with the aid of machine learning. At the moment the machine learning model has reached performance level comparable to the currently existing one, but we hope that we can eventually capture physical processes more realistically. In this talk, we will present some of the newest simulation results obtained with the machine learning KMC model, as well as some outlook on future work.

Primary authors

Jyri Kimari Ville Jansson (University of Helsinki) Simon Vigonski (University of Tartu) Ekaterina Baibuz (University of Helsinki) Dr Roberto Domingos (Rio de Janeiro State University) Vahur Zadin (University of Tartu (EE)) Flyura Djurabekova (Helsinki Institute of Physics (FI))

Presentation materials