Itinerant ferromagnetism of the Pd-terminated polar surface of PdCoO 2

DOI: 10.1073/pnas.1811873115

Authors: Federico Mazzola (University of St. Andrews) , Veronika Sunko (University of St. Andrews; Max Planck Institute for Chemical Physics of Solids) , Seunghyun Khim (Max Planck Institute for Chemical Physics of Solids) , Helge Rosner (Max Planck Institute for Chemical Physics of Solids) , Pallavi Kushwaha (Max Planck Institute for Chemical Physics of Solids) , Oliver J. Clark (University of St. Andrews) , Lewis Bawden (University of St. Andrews) , Igor Markovic (University of St. Andrews; Max Planck Institute for Chemical Physics of Solids) , Timur K. Kim (Diamond Light Source) , Moritz Hoesch (Diamond Light Source) , Andrew P. Mackenzie (Max Planck Institute for Chemical Physics of Solids; University of St. Andrews) , Phil D. C. King (University of St. Andrews)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Proceedings Of The National Academy Of Sciences , VOL 15

State: Published (Approved)
Published: December 2018
Diamond Proposal Number(s): 12469 , 14927 , 16262

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.

Journal Keywords: delafossite; itinerant ferromagnetism; electronic reconstruction; transition-metal oxide; angle-resolved photoemission

Subject Areas: Materials, Physics


Instruments: I05-ARPES