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DOE OSTI · 1832902

Large Nernst Effect and Thermodynamics Properties in Weyl Antiferromagnet

Tomita, Takahiro·Ikhlas, Muhammad·Nakatsuji, Satoru
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Abstract

The noncollinear antiferromagnet Mn3Sn exhibits a large anomalous Hall effect (AHE) driven by a large Berry curvature despite the vanishingly small magnetization. Theoretically, the large Berry curvature in antiferromagnets is predicted to be induced by the time-reversal breaking Weyl state in momentum space. Here, we comprehensively study the thermal conductivity, specific heat, thermoelectric power S(T), and thermomagnetic power S ji (T) in single crystals of Mn 3 Sn. Mn 3 Sn exhibited a large spontaneous anomalous Nernst effect (ANE) at room temperature; in particular, the signal magnitude of Mn 3 Sn exceeded 0.6 µV/K, which is comparable to that of ordinary ferromagnets. The large ANE results from the magnetic Weyl states near the Fermi level E F and likely shares its origin with the AHE. Moreover, the possibility of Nernst-type thermoelectric modules was evaluated by analyzing the basic thermal and electric physical properties.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSNernst effectantiferromagnetspintronicstopology

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Tomita, Takahiro, Ikhlas, Muhammad, Nakatsuji, Satoru. 2020-03-18. Large Nernst Effect and Thermodynamics Properties in Weyl Antiferromagnet. https://doi.org/10.7566/jpscp.30.011009

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