Transport in magnetic nanowires and topological microstructures
I investigate spin-dependent transport phenomena in magnetic and topological micro- and nanostructures by means of electrical conductivity σ, thermal conductivity κ and thermopower S measurements. Samples are synthesised by electrodeposition (e.g. multilayered nanowires) or defined from bulk structures (e.g. NbP). Measurement devices are fabricted by laser beam lithography followed by a metallization process. We perform transport measurements in a broad temperature range and with magnetic fields applied in various directions. Magnetoresistance, magneto-Seebeck and magneto-thermal conductivity measurements as well as Shubnikov-de-Haas measurements are part of our characterization tools.
Figure: A multilayered Co-Ni/Cu nanowire in a typical electrical contact structure for measureing the electrical resistivity/conductivity σ and the Seebeck coefficient S as a function of an externally applied magnetic field.
2016P. Sergelius, J. Gooth, S. Bassler, R. Zierold, C. Wiegand, A. Niemann, H. Reith, C. Shekhar, C. Felser, B.H. Yan, K. Nielsch: Berry phase and band structure analysis of the Weyl semimetal NbP, Scientific Reports 6 (2016), S. 33859/1-6 URL
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