Signatures of the Magnetic Entropy in the Thermopower Signals in Nanoribbons of the Magnetic Weyl Semimetal Co3Sn2S2

GEISHENDORF, KEVIN; VIR, PRAVEEN; SHEKHAR, CHANDRA; FELSER, CLAUDIA; FACIO, JORGE I.; VAN DEN BRINK, JEROEN; NIELSCH, KORNELIUS; THOMAS, ANDY; GOENNENWEIN, SEBASTIAN T. B.

NANO LETTERS (PRINT)

AMER CHEMICAL SOC

Año: 2019 vol. 20 p. 300 - 305

1530-6984

Weyl semimetals exhibit interesting electronic properties due to their topological band structure. In particular, large anomalous Hall and anomalous Nernst signals are often reported, which allow for a detailed and quantitative study of subtle features. We pattern single crystals of the magnetic Weyl semimetal Co3Sn2S2 into nanoribbon devices using focused ion beam cutting and optical lithography. This approach enables a very precise study of the galvano- and thermomagnetic transport properties. Indeed, we found interesting features in the temperature dependency of the anomalous Hall and Nernst effects. We present an analysis of the data based on the Mott relation and identify in the Nernst response signatures of magnetic fluctuations enhancing the anomalous Nernst conductivity at the magnetic phase transition.