Magnetotransport and thermopower of single Bi0.92Sb0.08 nanowires



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This Letter reports on temperature-dependent electrical measurements of single Bi0.92Sb0.08 nanowires with diameters between 220 nm and 350 nm. The magnetoresistance effect under transverse magnetic fields of ±2 T and the Seebeck coefficient S are measured in the temperature range of 50–300 K. Additionally, the influence of an annealing step on the transport properties is investigated. The as-prepared wires show heterogeneous temperature dependent behavior, whereas the annealed wires show semiconductive behavior. The room temperature value of the resistivity of the wires is between 2 × 10–6 Ωm and 1.4 × 10–5 Ωm. Magnetoresistance effects up to 15% at 50 K for the as-prepared nanowires and up to 23% for the annealed wires are observed. The temperature dependent Seebeck coefficient of single wires is determined. The as-prepared wires show a rise of the absolute value of S with temperature and it seems to saturate at room temperature. In contrast to this, the annealed wires show a linear increase of S. The room temperature values of S are –55 µV K–1 and –45 µV K–1, respectively. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)