title: Self-Diffusion in Amorphous Silicon.
abstract: The present Letter reports on self-diffusion in amorphous silicon. Experiments were done on ^{29}Si/^{nat}Si heterostructures using neutron reflectometry and secondary ion mass spectrometry. The diffusivities follow the Arrhenius law in the temperature range between 550 and 700 °C with an activation energy of (4.4±0.3)  eV. In comparison with single crystalline silicon the diffusivities are tremendously higher by 5 orders of magnitude at about 700 °C, which can be interpreted as the consequence of a high diffusion entropy.
authors.affiliation: AG Mikrokinetik, Institut für Metallurgie, TU Clausthal, D-38678 Clausthal-Zellerfeld, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Strauß
authors.affiliation: AG Mikrokinetik, Institut für Metallurgie, TU Clausthal, D-38678 Clausthal-Zellerfeld, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Dörrer
authors.affiliation: Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, Villigen CH-5232, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Geue
authors.affiliation: Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, Villigen CH-5232, Switzerland.
authors.forename: Jochen
authors.initials: J
authors.lastname: Stahn
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstraße 1, D-85747 Garching, Germany.
authors.forename: Alexandros
authors.initials: A
authors.lastname: Koutsioubas
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstraße 1, D-85747 Garching, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Mattauch
authors.affiliation: AG Mikrokinetik, Institut für Metallurgie, TU Clausthal, D-38678 Clausthal-Zellerfeld, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Schmidt