Observation of Anomalous Thermal Hall Effect in a Kagome Superconductor

Hiroki Yoshida; Hikaru Takeda; Jian Yan; Yui Kanemori; Brenden R. Ortiz; Yuzki M. Oey; Stephen D. Wilson; Marcin Konczykowski; Kota Ishihara; Takasada Shibauchi; Minoru Yamashita

doi:10.1126/sciadv.adu2973

arXiv · 2509.10630

Observation of Anomalous Thermal Hall Effect in a Kagome Superconductor

Hiroki Yoshida·Hikaru Takeda·Jian Yan·Yui Kanemori·Brenden R. Ortiz·Yuzki M. Oey·Stephen D. Wilson·Marcin Konczykowski·Kota Ishihara·Takasada Shibauchi·Minoru Yamashita

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Abstract

Broken time-reversal symmetry (TRS) in superconductors can induce not only spontaneous magnetization by the finite angular momentum of Cooper pairs, but also anomalous thermal Hall effects (ATHEs), whose detection has been extremely challenging. Here we report the successful observation of an ATHE developing below the superconducting transition temperature at zero magnetic field in the kagome-lattice superconductor CsV3Sb5. This finding is verified by the absence of a signal in a conventional type-II superconductor using the same setup and by ruling out the trapped-vortex effects through micro-Hall array measurements. Remarkably, both the temperature dependence and the magnitude of the observed anomalous thermal Hall conductivity are quite different from those expected for the quantized thermal edge current of an intrinsic ATHE, but consistent with extrinsic impurity-induced ATHEs in chiral superconductivity. Our study of ATHE offers an alternative approach to probe TRS breaking in the superconducting states.

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Hiroki Yoshida, Hikaru Takeda, Jian Yan, Yui Kanemori, Brenden R. Ortiz, Yuzki M. Oey, Stephen D. Wilson, Marcin Konczykowski, Kota Ishihara, Takasada Shibauchi, Minoru Yamashita. 2025-09-12. Observation of Anomalous Thermal Hall Effect in a Kagome Superconductor. https://doi.org/10.1126/sciadv.adu2973

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