High-mobility two-dimensional carriers from surface Fermi arcs in magnetic Weyl semimetal films

Shingo Kaneta-Takada; Yuki K. Wakabayashi; Yoshiharu Krockenberger; Toshihiro Nomura; Yoshimitsu Kohama; Sergey A. Nikolaev; Hena Das; Hiroshi Irie; Kosuke Takiguchi; Shinobu Ohya; Masaaki Tanaka; Yoshitaka Taniyasu; Hideki Yamamoto

arXiv · 2106.03292

High-mobility two-dimensional carriers from surface Fermi arcs in magnetic Weyl semimetal films

Shingo Kaneta-Takada·Yuki K. Wakabayashi·Yoshiharu Krockenberger·Toshihiro Nomura·Yoshimitsu Kohama·Sergey A. Nikolaev·Hena Das·Hiroshi Irie·Kosuke Takiguchi·Shinobu Ohya·Masaaki Tanaka·Yoshitaka Taniyasu·Hideki Yamamoto

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Abstract

High-mobility two-dimensional carriers originating from surface Fermi arcs in magnetic Weyl semimetals are highly desired for accessing exotic quantum transport phenomena and for topological electronics applications. Here, we demonstrate high-mobility two-dimensional carriers that show quantum oscillations in magnetic Weyl semimetal SrRuO3 epitaxial films by systematic angle-dependent, high-magnetic field magnetotransport experiments. The exceptionally high-quality SrRuO3 films were grown by state-of-the-art oxide thin film growth technologies driven by machine learning algorithm. The quantum oscillations for the 10-nm SrRuO3 film show a high quantum mobility of 3500 cm2/Vs, a light cyclotron mass, and two-dimensional angular dependence, which can be attributed to the surface Fermi arcs. The linear thickness dependence of the phase shift of the quantum oscillations provides evidence for the non-trivial nature of the quantum oscillations mediated by the surface Fermi arcs. In addition, at low temperatures and under magnetic fields of up to 52 T, the quantum limit of SrRuO3 manifests the chiral anomaly of the Weyl nodes. Emergence of the hitherto hidden two-dimensional Weyl states in a ferromagnetic oxide pave the way to explore novel quantum transport phenomena for topological oxide electronics.

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Shingo Kaneta-Takada, Yuki K. Wakabayashi, Yoshiharu Krockenberger, Toshihiro Nomura, Yoshimitsu Kohama, Sergey A. Nikolaev, Hena Das, Hiroshi Irie, Kosuke Takiguchi, Shinobu Ohya, Masaaki Tanaka, Yoshitaka Taniyasu, Hideki Yamamoto. 2021-06-07. High-mobility two-dimensional carriers from surface Fermi arcs in magnetic Weyl semimetal films. https://arxiv.org/abs/2106.03292

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