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arXiv · 1908.08173

Anomalous Hall effect at the spontaneously electron-doped polar surface of PdCoO2 ultrathin films

T. Harada·K. Sugawara·K. Fujiwara·S. Ito·T. Nojima·T. Takahashi·T. Sato·A. Tsukazaki
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Abstract

We revealed the electrical transport through surface ferromagnetic states of a nonmagnetic metal PdCoO2. Electronic reconstruction at the Pd-terminated surface of PdCoO2 induces Stoner-like ferromagnetic states, which could lead to spin-related phenomena among the highly conducting electrons in PdCoO2. Fabricating a series of nanometer-thick PdCoO2 thin films, we detected a surface-magnetization-driven anomalous Hall effect via systematic thickness- and termination-dependent measurements. Besides, we discuss that finite magnetic moments in electron doped CoO2 triangular lattices may have given rise to additional unconventional Hall resistance.

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T. Harada, K. Sugawara, K. Fujiwara, S. Ito, T. Nojima, T. Takahashi, T. Sato, A. Tsukazaki. 2019-08-22. Anomalous Hall effect at the spontaneously electron-doped polar surface of PdCoO2 ultrathin films. https://doi.org/10.1103/physrevresearch.2.013282

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