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arXiv · 1704.02241

Thermopower and thermal conductivity in the Weyl semimetal NbP

U. Stockert·R. D. dos Reis·M. O. Ajeesh·S. J. Watzman·M. Schmidt·C. Shekhar·J. P. Heremans·C. Felser·M. Baenitz·M. Nicklas
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Abstract

The Weyl semimetal NbP exhibits an extremely large magnetoresistance (MR) and an ultra-high mobility. The large MR originates from a combination of the nearly perfect compensation between electron- and hole-type charge carriers and the high mobility, which is relevant to the topological band structure. In this work we report on temperature- and field-dependent thermopower and thermal conductivity experiments on NbP. Additionally, we carried out complementary heat capacity, magnetization, and electrical resistivity measurements. We found a giant adiabatic magnetothermopower with a maximum of 800 $μ$V/K at 50 K in a field of 9 T. Such large effects have been observed rarely in bulk materials. We suggest that the origin of this effect might be related to the high charge-carrier mobility. We further observe pronounced quantum oscillations in both thermal conductivity and thermopower. The obtained frequencies compare well with our heat capacity and magnetization data.

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U. Stockert, R. D. dos Reis, M. O. Ajeesh, S. J. Watzman, M. Schmidt, C. Shekhar, J. P. Heremans, C. Felser, M. Baenitz, M. Nicklas. 2017-05-31. Thermopower and thermal conductivity in the Weyl semimetal NbP. https://doi.org/10.1088/1361-648x%2Faa7a3b

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