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arXiv · 2104.13536

Effective reduction of PdCoO2 thin films via hydrogenation and sign tunable anomalous Hall effect

Gaurab Rimal·Yiting Liu·Caleb Schmidt·Hussein Hijazi·Elizabeth Skoropata·Jason Lapano·Debangshu Mukherjee·Raymond R. Unocic·Matthew F. Chisholm·Yifei Sun·Haoming Yu·Cheng-Jun Sun·Hua Zhou·Matthew Brahlek·Leonard C. Feldman·Shriram Ramanathan·Seongshik Oh
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Abstract

PdCoO2 , belonging to a family of triangular oxides called delafossite, is one of the most conducting oxides. Its in-plane conductivity is comparable to those of the best metals, and exhibits hydrodynamic electronic transport with extremely long mean free path at cryogenic temperatures. Nonetheless, it is nonmagnetic despite the presence of the cobalt ion. Here, we show that a mild hydrogenation process reduces PdCoO2 thin films to an atomically-mixed alloy of PdCo with strong out-of-plane ferromagnetism and sign-tunable anomalous Hall effect. Considering that many other compounds remain little affected under a similar hydrogenation condition, this discovery may provide a route to creating novel spintronic heterostructures combining strong ferromagnetism, involving oxides and other functional materials.

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Gaurab Rimal, Yiting Liu, Caleb Schmidt, Hussein Hijazi, Elizabeth Skoropata, Jason Lapano, Debangshu Mukherjee, Raymond R. Unocic, Matthew F. Chisholm, Yifei Sun, Haoming Yu, Cheng-Jun Sun, Hua Zhou, Matthew Brahlek, Leonard C. Feldman, Shriram Ramanathan, Seongshik Oh. 2021-04-28. Effective reduction of PdCoO2 thin films via hydrogenation and sign tunable anomalous Hall effect. https://doi.org/10.1103/physrevmaterials.5.l052001

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