@article{oai:nifs-repository.repo.nii.ac.jp:00010820,
 author = {KATO,  Daiji and IWAKIRI,  Hirotomo and MORISHITA,  Kazunori and MUROGA,  Takeo},
 issue = {8},
 journal = {Nuclear Fusion},
 month = {Jul},
 note = {0000-0002-5302-073X, Tungsten is a prime candidate as the divertor material of the ITER and DEMO reactors, which would be exposed to unprecedentedly high-flux plasmas as well as neutrons. For a better characterization of radiation damages in the tungsten under the divertor condition, we examine influences of super-saturated hydrogen on vacancies in the tungsten. The present calculations based on density functional theory (DFT) reveal unusual phenomena predicted at a super-saturated hydrogen concentration: (1) strongly enhanced vacancy concentration with the super-saturated hydrogen concentration is predicted by a thermodynamics model assuming multiple-hydrogen trapping, i.e. hydrogen clusters formation, in the vacancies; and (2) DFT molecular dynamics revealed that hydrogen clusters can prevent a vacancy from recombining with the neighboring crowdion-type self-interstitial-atom. This suggests that neutron damage effects will be increased in the presence of the hydrogen clusters.},
 title = {Super-saturated hydrogen effects on radiation damages in tungsten under the high-flux divertor plasma irradiation},
 volume = {55},
 year = {2015}
}