title: Self-interstitial in germanium.
abstract: Low-temperature radiation damage in n- and p-type Ge is strikingly different, reflecting the charge-dependent properties of vacancies and self-interstitials. We find, using density functional theory, that in Ge the interstitial is bistable, preferring a split configuration when neutral and an open cage configuration when positively charged. The split configuration is inert while the cage configuration acts as a double donor. We evaluate the migration energies of the defects and show that the theory is able to explain the principal results of low-temperature electron-irradiation experiments.
authors.affiliation: School of Physics, University of Exeter, Stocker Road, Exeter, EX4 4QL, United Kingdom. carvalho@excc.ex.ac.uk
authors.forename: A
authors.initials: A
authors.lastname: Carvalho
authors.forename: R
authors.initials: R
authors.lastname: Jones
authors.forename: C
authors.initials: C
authors.lastname: Janke
authors.forename: J P
authors.initials: JP
authors.lastname: Goss
authors.forename: P R
authors.initials: PR
authors.lastname: Briddon
authors.forename: J
authors.initials: J
authors.lastname: Coutinho
authors.forename: S
authors.initials: S
authors.lastname: Oberg