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arXiv · 2112.00282

Anomalous Nernst Effect in Nonmagnetic Nodal Line Semimetal PbTaSe$_2$

K. Yokoi·H. Murakawa·H. Sakai·N. Hanasaki
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Abstract

PbTaSe$_2$ is a unique topological material, in which the number of nodal lines is expected to change at the structural transition between the lower temperature/pressure "L" phase and the higher temperature/pressure "H" phase. We report the anomalous Nernst effect attributed to the Berry curvature of nodal lines and its change with the structural transition. In the L phase, the Nernst coefficient ($S_{yx}$) shows the step-like magnetic field dependence reminiscent of the anomalous Nernst effect of nonmagnetic Dirac/Weyl semimetals. By applying hydrostatic pressure, we discovered that the amplitude of the anomalous component significantly decreases at the transition to the H phase, which might correspond to the partial annihilation of nodal line structures.

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K. Yokoi, H. Murakawa, H. Sakai, N. Hanasaki. 2021-12-01. Anomalous Nernst Effect in Nonmagnetic Nodal Line Semimetal PbTaSe$_2$. https://doi.org/10.1103/physrevb.106.115118

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