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arXiv · 2306.01979

Thickness-dependent, tunable anomalous Hall effect in hydrogen-reduced PdCoO$_2$ thin films

Gaurab Rimal·Yiting Liu·Matthew Brahlek·Seongshik Oh
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Abstract

It was recently reported that hydrogen-reduced PdCoO$_2$ films exhibit strong perpendicular magnetic anisotropy (PMA) with sign tunable anomalous Hall effect (AHE). Here, we provide extensive thickness-dependent study of this system, and show that the electronic and magnetic properties are strongly dependent on the thickness and annealing conditions. Below a critical thickness of 25 nm, AHE shows clear PMA with hysteresis, and its sign changes from positive to negative, and back to positive as the annealing temperature increases from 100 $^\circ$C to 400 $^\circ$C. Beyond the critical thickness, both PMA and AHE hysteresis disappear and the AHE sign remains positive regardless of the annealing parameters. Our results show that PMA may have a large role on AHE sign-tunability and that below the critical thickness, competition between different AHE mechanisms drives this sign change.

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Gaurab Rimal, Yiting Liu, Matthew Brahlek, Seongshik Oh. 2023-06-03. Thickness-dependent, tunable anomalous Hall effect in hydrogen-reduced PdCoO$_2$ thin films. https://arxiv.org/abs/2306.01979

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