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

发表信息：: Phys. Rev. Research 2, 013282 (2020)
DOI：: 10.1103/PhysRevResearch.2.013282

英文摘要：

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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