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Abstract The band structure of ultrathin Pd(111) thin films grown on the Cr2O3(0001) surface was studied by angule-resolved photoemission spectroscopy (ARPES) combined with first-principles calculations. The Cr2O3(0001) interface and the expanded Pd lattice constant appears to significantly affect the occupied band structure of an ultrathin palladium film. A characteristic band splitting is seen in the experimental occupied electronic structure, forming a hexagonal pattern approximately half-way from the point to the surface Brillouin zone boundary. The ARPES spectrum near the Fermi level is reproduced by the first-principles simulation for a Pd monolayer (ML) placed on the Cr-terminated Cr2O3surface with the energetically favorable lateral stacking. In this configuration, the Pd bands inside the Cr2O3band gap have a significant, momentum-dependent exchange splitting, which matches with the experimentally observed band splitting. The experimental band structure shows a band with an electron effective mass close to the free electron mass, neglecting mass enhancement effects close to the Fermi level. From the hybridization of the Pd ML with the Cr2O3(0001) substrate, a hole band with a mass of −0.48 ± 0.02 is identified.
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This content will become publicly available on November 1, 2026
Altermagnetic Band Splitting in 10 nm Epitaxial CrSb Thin Films
Abstract Altermagnets are a newly identified family of collinear antiferromagnets with a momentum‐dependent spin‐split band structure of non‐relativistic origin, derived from spin‐group symmetry‐protected crystal structures. Among candidate altermagnets, CrSb is attractive for potential applications because of a large spin‐splitting near the Fermi level and a high Néel transition temperature of around 700 K. Molecular beam epitaxy is used to synthesize CrSb (0001) thin films with thicknesses ranging from 10 to 100 nm. Structural characterization, using reflection high energy electron diffraction, scanning transmission electron microscopy, and X‐ray diffraction, demonstrates the growth of epitaxial films with good crystallinity. Polarized neutron reflectometry shows the absence of any net magnetization, consistent with antiferromagnetic order.In vacuoangle resolved photoemission spectroscopy (ARPES) measurements probe the band structure in a previously unexplored regime of film thickness, down to 10 nm. These ARPES measurements show a bulk‐type, 3D momentum‐dependent band splitting of up to 0.7 eV with g‐wave symmetry, consistent with that seen in prior studies of bulk single crystals. The distinct altermagnetic band structure required for potential spin‐transport applications survives down to the ∼10 nm thin film limit at room temperature.
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- PAR ID:
- 10681142
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 37
- Issue:
- 47
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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