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Itinerant ferromagnetism of the Pd-terminated polar surface of PdCoO2.

ABSTRACT: The ability to modulate the collective properties of correlated electron systems at their interfaces and surfaces underpins the burgeoning field of "designer" quantum materials. Here, we show how an electronic reconstruction driven by surface polarity mediates a Stoner-like magnetic instability to itinerant ferromagnetism at the Pd-terminated surface of the nonmagnetic delafossite oxide metal PdCoO2 Combining angle-resolved photoemission spectroscopy and density-functional theory calculations, we show how this leads to a rich multiband surface electronic structure. We find similar surface state dispersions in PdCrO2, suggesting surface ferromagnetism persists in this sister compound despite its bulk antiferromagnetic order.

SUBMITTER: Mazzola F

PROVIDER: S-EPMC6304953 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Itinerant ferromagnetism of the Pd-terminated polar surface of PdCoO<sub>2</sub>.

Mazzola Federico F Sunko Veronika V Khim Seunghyun S Rosner Helge H Kushwaha Pallavi P Clark Oliver J OJ Bawden Lewis L Marković Igor I Kim Timur K TK Hoesch Moritz M Mackenzie Andrew P AP King Phil D C PDC

Proceedings of the National Academy of Sciences of the United States of America 20181204 51

The ability to modulate the collective properties of correlated electron systems at their interfaces and surfaces underpins the burgeoning field of "designer" quantum materials. Here, we show how an electronic reconstruction driven by surface polarity mediates a Stoner-like magnetic instability to itinerant ferromagnetism at the Pd-terminated surface of the nonmagnetic delafossite oxide metal PdCoO<sub>2</sub> Combining angle-resolved photoemission spectroscopy and density-functional theory calc ...[more]

PMID: 30514820

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