Anomalous thermal Hall effect in the topological antiferromagnetic state

Kaori Sugii; Yusuke Imai; Masaaki Shimozawa; Muhammad Ikhlas; Naoki Kiyohara; Takahiro Tomita; Michi-To Suzuki; Takashi Koretsune; Ryotaro Arita; Satoru Nakatsuji; Minoru Yamashita

arXiv · 1902.06601

Anomalous thermal Hall effect in the topological antiferromagnetic state

Kaori Sugii·Yusuke Imai·Masaaki Shimozawa·Muhammad Ikhlas·Naoki Kiyohara·Takahiro Tomita·Michi-To Suzuki·Takashi Koretsune·Ryotaro Arita·Satoru Nakatsuji·Minoru Yamashita

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Abstract

The anomalous Hall effect (AHE), a Hall signal occurring without an external magnetic field, is one of the most significant phenomena. However, understanding the AHE mechanism has been challenging and largely restricted to ferromagnetic metals. Here, we investigate the recently discovered AHE in the chiral antiferromagnet Mn3Sn by measuring a thermal analog of the AHE, known as an anomalous thermal Hall effect (ATHE). The amplitude of the ATHE scales with the anomalous Hall conductivity of Mn3Sn over a wide temperature range, demonstrating that the AHE of Mn3Sn arises from a dissipationless intrinsic mechanism associated with the Berry curvature. Moreover, we find that the dissipationless AHE is significantly stabilized by shifting the Fermi level toward the magnetic Weyl points. Thus, in Mn3Sn, the Berry curvature emerging from the proposed magnetic Weyl fermion state is a key factor for the observed AHE and ATHE.

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Kaori Sugii, Yusuke Imai, Masaaki Shimozawa, Muhammad Ikhlas, Naoki Kiyohara, Takahiro Tomita, Michi-To Suzuki, Takashi Koretsune, Ryotaro Arita, Satoru Nakatsuji, Minoru Yamashita. 2019-02-18. Anomalous thermal Hall effect in the topological antiferromagnetic state. https://arxiv.org/abs/1902.06601

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