About this Journal Submit a Manuscript Table of Contents
Journal of Nanotechnology
Volume 2012 (2012), Article ID 480813, 5 pages
http://dx.doi.org/10.1155/2012/480813
Research Article

Thermoelectric Characterization of Electronic Properties of GaMnAs Nanowires

1Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, P.O. Box 118, 221 00 Lund, Sweden
2Department of Mathematics, Physics, and Electrical Engineering, Halmstad University, P.O. Box 823, 301 18 Halmstad, Sweden
3Institute for Solid State Physics, Jena University, Max-Wien-Platz 1, 07743 Jena, Germany
4Division of Physics, School of Computer Science, Physics and Mathematics, Linnæus University, 39233 Kalmar, Sweden

Received 21 June 2012; Accepted 23 August 2012

Academic Editor: Magnus T. Borgstrom

Copyright © 2012 Phillip M. Wu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Nanowires with magnetic doping centers are an exciting candidate for the study of spin physics and proof-of-principle spintronics devices. The required heavy doping can be expected to have a significant impact on the nanowires' electron transport properties. Here, we use thermopower and conductance measurements for transport characterization of Ga0.95Mn0.05As nanowires over a broad temperature range. We determine the carrier type (holes) and concentration and find a sharp increase of the thermopower below temperatures of 120 K that can be qualitatively described by a hopping conduction model. However, the unusually large thermopower suggests that additional mechanisms must be considered as well.