title: The surface-to-volume ratio: a key parameter in the thermoelectric transport of topological insulator Bi2Se3 nanowires.
abstract: We systematically investigated the role of topological surface states on thermoelectric transport by varying the surface-to-volume ratio (s/v) of Bi2Se3 nanowires. The thermoelectric coefficients of Bi2Se3 nanowires were significantly influenced by the topological surface states with increasing the s/v. The Seebeck coefficient of Bi2Se3 nanowires decreased with increasing the s/v, while the electrical conductivity increased with increasing the s/v. This implies that the influence of metallic surface states become dominant in thermoelectric transport in thin nanowires, and the s/v is a key parameter which determines the total thermoelectric properties. Our measurements were corroborated by using a two-channel Boltzmann transport model.
authors.affiliation: Institute of Nanostructure and Solid State Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany. hshin@physnet.uni-hamburg.de.
authors.forename: Ho Sun
authors.initials: HS
authors.lastname: Shin
authors.affiliation: Institute of Nanostructure and Solid State Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany. hshin@physnet.uni-hamburg.de.
authors.forename: Bacel
authors.initials: B
authors.lastname: Hamdou
authors.affiliation: Institute of Metallic Materials, Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069 Dresden, Germany. k.nielsch@ifw-dresden.de.
authors.forename: Heiko
authors.initials: H
authors.lastname: Reith
authors.affiliation: Institute of Nanostructure and Solid State Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany. hshin@physnet.uni-hamburg.de.
authors.forename: Hermann
authors.initials: H
authors.lastname: Osterhage
authors.affiliation: Institute of Nanostructure and Solid State Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany. hshin@physnet.uni-hamburg.de.
authors.forename: Johannes
authors.initials: J
authors.lastname: Gooth
authors.affiliation: Institute of Metallic Materials, Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069 Dresden, Germany. k.nielsch@ifw-dresden.de.
authors.forename: Christine
authors.initials: C
authors.lastname: Damm
authors.affiliation: Institute of Metallic Materials, Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069 Dresden, Germany. k.nielsch@ifw-dresden.de.
authors.forename: Bernd
authors.initials: B
authors.lastname: Rellinghaus
authors.affiliation: Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
authors.forename: Eckhard
authors.initials: E
authors.lastname: Pippel
authors.affiliation: Institute of Metallic Materials, Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069 Dresden, Germany. k.nielsch@ifw-dresden.de.
authors.forename: Kornelius
authors.initials: K
authors.lastname: Nielsch