PLEASE NOTE NEW EMAIL ADDRESS: thomas.swinburne cnrs.fr
The design of more durable materials is key to reduce the carbon emissions of construction, transportation and energy production. This requires an understanding of mechanical strength and toughness at the level of jiggling atoms.
We design atomic simulation methods to discover how metals bend and break.
The range of atomic deformation mechanisms is vast- the challenge is to discover and characterize the most influential. A short summary is below; for more detail please see our publications and open source software.
News
Main Research Themes
![]() |
Autonomous exploration at scale: TAMMBER
In massively parallel computatation, decisions must be made every few minutes
to optimise resources. TAMMBER uses novel Bayesian methods to autonomously
allocate computational effort only in the most relevant regions of configuration space,
building kMC/Markov models with robust UQ.
|
![]() |
ML-assisted DFT for dislocation-defect interations
(Postdoc of Petr Grigorev, from ANR JCJC MeMoPas) |
![]() |
Vibrational free energies beyond harmonicity: PAFI
PAFI is a path-constrained sampling routine, which returns exact vibrational
free energy differences for linear-scaling effort. This enables evaluation of
activation free energies for very large systems of e.g. dislocation or twin
migration, which can not be treated by cubic-scaling HTST approximations.
TDS† and M-C Marinica, PRL (2018)
PAFI |
![]() |
Surrogate ML models for defect entropics
(PhD of Clovis Lapointe, with M-C Marinica) |
![]() |
Analysis of Markov Models: PyGT
Much atomic data (from TAMMBER or other codes) is a connected network of metastable states, which
can be mapped to a discrete state Markov model, or master equation. We have developed tools to automatically propagate atomic data, with UQ, to drift-diffusion equations or first passage distributions between distant regions.
|
![]() |
Mean-field models for lattice vibrations: BLaSa
BLaSa is a lightening-fast mean field approach to evaluate anharmonic vibrational phase free energies for
milliseconds of effort. For unary FCC we are within meV/atom of brute force
thermodynamic integration, requiring hours of effort. Current developments are within the PhD of R Dsouza since 2020. |
Team
|
![]() |
10/18-: CNRS researcher, CINaM 04/17-06/18: Postdoc, T-1, LANL 03/15-03/17: EuroFusion fellow, CCFE 10/11-03/15: MSc+PhD, Imperial College London Curriculum Vitae |
|
![]() |
20-23: Postdoc, Machine learning assisted DFT methods Funded by ANR MEMOPAS (PI: TDS) Personal Website |
|
09/20-09/23: PhD, mean field vibration models. External with Prof J Neugebauer, MPIE Dusseldorf |
Main Collaborators
|
Analysis and convergence of highly metastable systems; Markov models e.g. JCTC 2020 PyGT |
|
Linear machine learning models, free energy calculation e.g. PRMat 2020 PRL 2018 PAFI |
|
Massively parallel sampling of metastable systems e.g. NPJ Comp. Mat 2020 TAMMBER |
|
Hybrid DFT/empirical methods e.g. PRB 2017 arXiv 2021/2 LML-retrain |
|
Mean field models for anharmonic lattice vibrations PRB RC 2020 BLaSa |
Past Members
|
09/18-02/22: PhD, Machine learning for defect entropics. Joint with Dr MC Marinica, CEA Saclay | |
|
21-21: M2 project, Learning of transition states, Aix-Marseille University. | |
|
![]() |
20-21: MSc project, reducing Markov Chains. With Prof DJ Wales, Cambridge. Now PhD, MIT. |
Recent Publications
† = corresponding author(s). Full list at Google Scholar.Software
- PAFI- Projected Average Force Integrator
- Anharmonic free energy barrier evaluations using in LAMMPS/MPI/C++
Physical Review Letters 2018
Works using PAFI (more coming soon...) Y Sato et al., D Rodney MRL (2021)
- TAMMBER- Temperature Accelerated Markov Models, Bayesian Estimation of Rates
- Massively parallel, autonmous exploration of atomic systems
Physical Review Materials 2018
TDS† and D Perez, NPJ Computational Materials (2020)
Works using TAMMBER (more coming soon...) K Ferasat et al., Materialia (2021) - PyGT- Graph Transformation in Python
- Stable analysis of metastable Markov chains
J Chem. Th. Comp. 2020
Works using PyGT (more coming soon...) TDS et al. JCP (2020)
D Kannan et al. JCP (2021)
- BLaSa- Bond Lattice Sampling and Analytics
- Execution and analysis of bond lattice dynamics
Physical Review B Rapid Communications 2020
Funding
- ANR MeMoPas (2020-2022)
PI on ANR JCJC project, Mesoscale models from massively parallel atomistic simulations: uncertainty driven, self-optimizing strategies for hard materials
- EuroFusion / IREMEV program
Computational resources (2020-2021) for studies of timescale estimation of microstructural evolution
- GENCI / IDRIS national supercomputing centers
Computational resources (2019-2020,2020-2021) for high-throughput studies of defect diffusion mechanisms



Job Openings
Some Presentations
- Kink limited motion of line defects: multiscale simulation and analysis
- Applied analysis seminar, Imperial College London, February 2019 (Invited) Slides
- Kink limited Orowan strengthening and the brittle to ductile transition of bcc metals
- Oxford MFFP Meeting, September 2018 (Invited) Slides
- Uncertainty-driven construction of Markov models from accelerated molecular dynamics
- Advances in Computational Statistical Physics, CIRM, France, September 2018 (Invited) Slides
- Fast, vacancy-free climb of dislocation loops in bcc metals
- NUMAT conference, Montpellier, France, 2016 Slides
- Multiscale analysis of nonlinear dislocation models
- MMM conference, Berkeley, USA, 2014 Slides