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arXiv · 1603.01258

Giant isotropic Nernst effect in an anisotropic Kondo semimetal

Ulrike Stockert·Peije Sun·Niels Oeschler·Frank Steglich·Toshiro Takabatake·Piers Coleman·Silke Paschen
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Abstract

The "failed Kondo insulator" CeNiSn has long been suspected to be a nodal metal, with a node in the hybridization matrix elements. Here we carry out a series of Nernst effect experiments to delineate whether the severely anisotropic magnetotransport coefficients do indeed derive from a nodal metal or can simply be explained by a highly anisotropic Fermi surface. Our experiments reveal that despite an almost 20-fold anisotropy in the Hall conductivity, the large Nernst signal is isotropic. Taken in conjunction with the magnetotransport anisotropy, these results provide strong support for an isotropic Fermi surface with a large anisotropy in quasiparticle mass derived from a nodal hybridization.

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Ulrike Stockert, Peije Sun, Niels Oeschler, Frank Steglich, Toshiro Takabatake, Piers Coleman, Silke Paschen. 2016-03-03. Giant isotropic Nernst effect in an anisotropic Kondo semimetal. https://doi.org/10.1103/physrevlett.117.216401

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