title: Structure and passivation effects of mono- and dihydrogen complexes in GaAsyN(1-y) alloys.
abstract: In GaAsyN(1-y), the presence of a few percent of N induces a large reduction of the GaAs band gap that vanishes upon hydrogenation. In the present Letter, the energetics of N-H complexes and their effects on the band structure of the GaAs0.97N0.03 alloy have been investigated by first-principles density functional methods. We find that monohydrogen N-H+ and dihydrogen N-H* 2 complexes are formed depending on doping. Moreover, only N-H* 2 complexes account for the neutralization of nitrogen effects. A model is proposed that clarifies the passivation mechanism of nitrogen by H.
authors.affiliation: CNR-Istituto di Struttura della Materia (ISM), Via Salaria Km 29.5, CP 10, 00016 Monterotondo Stazione, Italy. aldo.amore@mlib.cnr.it
authors.forename: A Amore
authors.initials: AA
authors.lastname: Bonapasta
authors.forename: F
authors.initials: F
authors.lastname: Filippone
authors.forename: P
authors.initials: P
authors.lastname: Giannozzi
authors.forename: M
authors.initials: M
authors.lastname: Capizzi
authors.forename: A
authors.initials: A
authors.lastname: Polimeni