Description Introduction: Plasma-wall interaction in fusion devices encompasses a wide variety of processes. On a short timescale these include deposition of energetic plasma particles (primarily hydrogen and helium) into the surface, physical and chemical sputtering of surface material into the plasma, and reflection and desorption of particles from the surface. On a longer timescale the processes include diffusion of hydrogen and helium in the wall and changes in surface composition, morphology and material microstructure due to plasma bombardment and (in a reactor) neutron irradiation. Together these processes are extremely important in determining the plasma performance, the lifetime of plasma-facing components, trapping and retention of the tritium fusion fuel in the wall, and ultimately the feasibility of fusion power production. The gap between what is known about plasma-material interaction and what is needed to design a fusion reactor is most severe for the effects of radiation damage on hydrogen retention properties of plasma-facing materials. Computations are particularly important for this problem, because experiments cannot fully simulate the radiation conditions in a fusion device. Appropriate computational materials tools range from statistical or otherwise averaged (binary collision approximation, kinetic Monte Carlo) and mechanical (molecular dynamics) models to semiempirical (tight binding) density functional theory codes and first principles quantum mechanical codes for inhomogeneous materials. Any of these codes has its own needs for fundamental data, which are in many cases obtained by parameterization of results of other calculations.

Purpose: The conference is intended to bring together researchers from the areas of fusion energy science and materials science in order to review advances in computational studies of plasma-material interaction processes and the evolution of material microstructure in fusion devices. Within this area the programme will emphasize work that is relevant to hydrogen (tritium) trapping and transport in candidate fusion reactor wall materials. This includes modelling of the effects of irradiation upon material microstructure and modelling to understand the influence of microstructure on hydrogen trapping and transport. Participants with a background in plasma-wall interaction in fusion experiments should return from the conference with a richer understanding of the wide range of computational methods that are used for development of plasma-material interaction data and material properties data for fusion plasma and fusion materials modelling. Participants from the area of materials science should obtain guidance about new work that is most needed to improve understanding of plasma-material interaction processes and material damage processes that are relevant for fusion energy development. The conference format is meant to encourage new collaborations on computational studies of plasma-material interaction in fusion devices.

Topics: The conference programme will emphasize uses of the more fundamental computational tools (based on quantum mechanics) and parameterization of results from such tools in the form of interaction potentials and transition rates for applied studies. Specific topics include the following.

* Direct uses of ab initio and semi-empirical quantum mechanical codes for study of materials microstructure, trapping and transport of hydrogen and helium in fusion wall materials.
* Optimization of parameters in semi-empirical codes and parameterization of results of quantum mechanical calculations in the form of interaction potentials and transition rates for classical models.
* Molecular Dynamics, Binary Collision Approximation and Kinetic Monte Carlo studies of plasma-material interaction, radiation damage processes and material and surface evolution.
* Multi-method and multi-scale simulations; acceleration approaches.
* Uncertainty estimation and uncertainty propagation from quantum mechanical calculations through interaction potentials to outputs of longer time-scale calculations.
* Parameterization of material microstructure and its effect on mobility and trapping of hydrogen and helium in fusion wall materials.
* Simulation and interpretation of diagnostics of material microstructure, radiation damage, hydrogen and helium in fusion materials and plasma-material interaction Participants will be active researchers in the subject area of the conference and we expect a scientific contribution (talk or poster) from each participant. 
Go to day
  • Monday, 3 November 2014
    • 08:30 - 20:00 Session
      • 08:30 Registration and Administrative Formalities 30' ( Leonardo da Vinci Building, Lobby )
        After you have registered with the activity secretary: 
        
        - ADMINISTRATIVE FORMALITIES (daily living allowances/travel reimbursements, bank transactions, etc.) at the Operations Office, E. Fermi Building - just above the Leonardo Da Vinci Bldg. 
        
        - MEAL COUPONS: balance will be issued by the Guesthouse Receptions one day after the on-line registration is completed according to the following timetables: 
        Galileo Guesthouse: 
        Tuesday to Friday 10.00-12.00 & 13.00-15.00 
        Adriatico Guesthouse: 
        Tuesday To Friday 13.00-15.00
      • 09:00 Welcome 15'
        Speakers: Sandro Scandolo (ICTP), Bas Braams (IAEA), Hyun-Kyung Chung (IAEA)
      • 09:15 Hydrogen isotope retention and release in beryllium: The full picture from experiment and ab initio calculations 45'
        Speaker: Christian Linsmeier (FZ Jülich, Germany)
        Material: Abstract
      • 10:00 Coffee Break 45'
      • 10:45 Multiscale modelling of hydrogen and helium in tungsten 45'
        Speaker: Kai Nordlund (University of Helsinki, Finland)
        Material: Abstract
      • 11:30 Challenges and strategies to experimental validation of multi-scale nuclear fusion PMI computational modeling 25'
        Speaker: Jean Paul Allain (UIUC, Illinois, USA)
        Material: Abstract
      • 11:55 Statistical study of defects caused by primary knock-on atoms in fcc and bcc metals using molecular dynamics simulations 25'
        Speaker: Manoj Warrier (Bhabha Atomic Research Center, Autonagar, Visakhapatnam, India)
        Material: Abstract Slides
      • 12:20 Lunch Break 1h40'
      • 14:00 Modelling the electronic excitation induced structural dynamics of tungsten 25'
        Speaker: Dorothy Duffy (UCL, London, United Kingdom)
        Material: Abstract
      • 14:25 Trapping of He clusters by inert-gas impurities in refractory bcc transition metals: systematic first-principles predictions and experimental validations 25'
        Speaker: Duc Nguyen-Manh (CCFE, Abingdon, United Kingdom)
        Material: Abstract
      • 14:50 Development of a potential model for tritium behavior in tungsten 25'
        Speaker: Takuji Oda (SNU, Seoul, Korea)
        Material: Abstract
      • 15:15 Coffee Break 1h0'
      • 16:15 Atomistic models for tungsten based alloys 25'
        Speaker: Paul Erhart (Chalmers UT, Gothenburg, Sweden)
        Material: Abstract
      • 16:40 Energy landscape of radiation-induced point defects in body centered cubic metals 25'
        Speaker: Mihai-Cosmin Marinica (CEA, Gif-sur-Yvette, France)
        Material: Abstract
      • 17:05 Brief review of PMI issues for DEMO, introduction to a discussion 25'
        Speaker: Christian Linsmeier (FZ Jülich, Germany)
      • 18:00 WELCOME RECEPTION 2h0'
  • Tuesday, 4 November 2014
    • 08:30 - 17:55 Session
      • 08:30 Helium gas clustering dynamics in tungsten exposed to helium plasmas 25'
        Speaker: Brian Wirth (UT, Knoxville, USA)
        Material: Abstract
      • 08:55 Calculation of defects and hydrogen in tungsten: fundamental parameters and methodological aspects 25'
        Speaker: Maria Ganchenkova (MEPhI, Moscow, Russia)
        Material: Abstract
      • 09:20 The capillarity equation at the nanoscale: size effects on gas bubbles in metals 25'
        Speaker: Alfredo Caro (LANL, Los Alamos, USA)
        Material: Abstract
      • 09:45 Coffee break 1h0'
      • 10:45 The atomistic phenomena at the plasma-surface interfaces 25'
        Speaker: Predrag Krstic (SUNY, Stony Brook, USA)
        Material: Abstract
      • 11:10 Techniques in uncertainty quantification and initial application to plasma-material interfaces 25'
        Speaker: Robert Harrison (SUNY and BNL, Brookhaven, USA)
      • 11:35 Minitalks to introduce the posters 25'
        Speaker: Posters Authors
      • 12:00 Lunch Break 2h0'
      • 14:00 Poster Session 2h0'
        Material: Lungu M. Warrier
      • 16:00 Coffee Break 30'
      • 16:30 ICTP Colloquium: Seeking a Sustainable Model for Scientific Simulation 1h0' ( LB - Budinich Lecture Hall )
        Speaker: Robert Harrison (SUNY and BNL, Brookhaven, USA)
        Material: Abstract
  • Wednesday, 5 November 2014
    • 08:30 - 17:55 Session
      • 08:30 Modelling the growth of He bubbles and trap mutation in tungsten 25'
        Speaker: Charlotte Becquart (University of Lille, France)
        Material: Abstract
      • 08:55 H trapping and migration in W: A DFT investigation that includes temperature dependency 25'
        Speaker: Yves Ferro (Aix-Marseille University, France)
        Material: Abstract
      • 09:20 Multiple hydrogen trapping by vacancies: its impact on defect dynamics and hydrogen retention in tungsten 25'
        Speaker: Daiji Kato (NIFS, Toki-City, Japan)
        Material: Abstract
      • 09:45 Coffee Break 1h0'
      • 10:45 Constructing interatomic potentials from first principles using machine learning: the example of tungsten. 25'
        Speaker: Gábor Csányi (University of Cambridge, U.K.)
        Material: Abstract
      • 11:10 Electrophobic interaction: the leading mechanism for helium self-trapping in metals 25'
        Speaker: Hong-Bo Zhou (Beihang University, Beijing, China)
        Material: Abstract
      • 11:35 Many-body decomposition of the interaction energy in lowest beryllium clusters Be3-8 25'
        Speaker: Miroslav Urban (Slovak University of Technology in Bratislava, Slovak Republic)
        Material: Abstract
      • 12:00 Lunch Break 2h0'
      • 14:00 Helium interaction with tungsten surfaces and subsequent evolution from atomistic simulations 25'
        Speaker: Alexander Barashev (ORNL, Oak Ridge, TN, USA)
        Material: Abstract
      • 14:25 Discussion Session I 1h15'
        on electronic structure computations and the development of MD potentials. 
        
        Questions:
        1a: What is the role of electronic excited states and how can effects of electronic excitation be included in the models and data?
        
        1b: Are we satisfied with present strategies for the development of MD potentials from electronic structure calculations?
      • 15:45 Coffee Break 1h0'
  • Thursday, 6 November 2014
    • 08:30 - 17:30 Session
      • 08:30 Migration of rhenium and osmium in tungsten 25'
        Speaker: Tomoaki Suzudo (JAEA, Tokai-mura, Japan)
        Material: Abstract
      • 08:55 Primary defect production in displacement cascades in beryllium 25'
        Speaker: Vladimir Borodin (RNC "Kurchatov Institute" and MEPhI, Moscow,Russia)
        Material: Abstract
      • 09:20 Design of composite materials for outgassing of implanted He 25'
        Speaker: Mike Demkowicz (MIT, Cambridge, USA)
        Material: Abstract Slides
      • 09:45 Growth of helium bubbles in tungsten under realistic rates 25'
        Speaker: Luis Sandoval (LANL, Los Alamos National Laboratory, USA)
        Material: Abstract
      • 10:10 Coffee Break 1h0'
      • 11:10 Calculating the release fraction of W tendrils into the plasma using polymeric reptation theory 25'
        Speaker: Jaime Marian (University of California, Los Angeles, USA)
        Material: Abstract
      • 11:35 Lunch Break 1h25'
      • 13:00 Discussion Session II 1h30'
        on long-time evolution calculations and the development of KMC rates. 
        
        Questions:
        
        2a: What is the role of nuclear quantum effects and how can these effects be included in the models and data?
        
        2b: Is it desirable and feasible to develop standard definitions for the objects in KMC models?
      • 14:30 Coffee Break 1h0'
  • Friday, 7 November 2014
    • 08:30 - 16:30 Session
      • 08:30 Present status of plasma-surface interaction investigations for EAST and CFETR 25'
        Speaker: Zhongshi Yang (CAS-IPP, Hefei, China)
        Material: Abstract
      • 08:55 Comparison of a quantitative diffusion-trap model with experiments on D uptake in damaged W 25'
        Speaker: Armin Manhard (IPP Garching, Germany)
        Material: Abstract
      • 09:20 Bridging model and real systems with laboratory experiments: dynamic retention of deuterium in tungsten 15'
        Speaker: Régis Bisson (Aix-Marseille Université, Marseille, France)
        Material: Abstract
      • 09:35 In situ study of isotope exchange mechanism in self-ion damaged tungsten 15'
        Speaker: Sabina Markelj (Josef Stefan Institute, Ljubljana, Slovenia)
        Material: Abstract
      • 09:50 Coffee Break 55'
      • 10:45 Hydrogen atom recombination on tungsten at high temperature: a combined experimental and theoretical work 15'
        Speaker: Maria Rutigliano (CNR-IMIP, Bari, Italy)
        Material: Abstract
      • 11:00 Periodic structures formation on beryllium, carbon, tungsten films mixed films by TW laser irradiation 15'
        Speaker: Petrica Cristian Lungu (INFLPR, Magurele, Romania)
      • 11:15 Effect of thermal and collisional processes on the performance of plasma-facing components in mixed materials environment 15'
        Speakers: Author: Ahmed Hassanein (Purdue University, USA), Presented by Predrag Krstic
      • 11:30 Discussion Session III 1h30'
        on uncertainties in comprehensive modelling for present and future experiments.
        
        Questions:
        
        3a: What are the most important model uncertainties for calculation of damage in fusion wall materials (primarily tungsten and steel) by neutrons and fast particles?
        
        3b: What are the most important model uncertainties for calculation of hydrogen trapping and transport in fusion wall materials?
        
        3c: What are some priorities for experimental information to help assess errors
      • 13:00 Lunch Break 1h0'