title: Vacancy migrations in carbon nanotubes.
abstract: Activities of vacancy defects in carbon nanotubes have been directly monitored by in situ high-resolution transmission electron microscopy at elevated temperatures. Adatom-vacancy pair defects are first prolific due to the knock-on damage, and then the induced vacancies indeed grow up to 1-2 nm in the size by the following Joule heating. Surprisingly, these large vacancies, or "holes", tend to migrate and coalesce with each other to form even larger ones. It suggests that the activation barrier has been substantially lowered due to the contributions of an electromigration and/or irradiation effect.
authors.affiliation: Research Center for Advanced Carbon Materials, National Institute of AdvancedIndustrial Science and Technology, Central 5, Tsukuba 305-8565, Japan. chuanhong-jin@aist.go.jp
authors.forename: Chuanhong
authors.initials: C
authors.lastname: Jin
authors.forename: Kazu
authors.initials: K
authors.lastname: Suenaga
authors.forename: Sumio
authors.initials: S
authors.lastname: Iijima