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Direct observation of localized spin antiferromagnetic transition in PdCrO2 by angle-resolved photoemission spectroscopy.

ABSTRACT: We report the first case of the successful measurements of a localized spin antiferromagnetic transition in delafossite-type PdCrO2 by angle-resolved photoemission spectroscopy (ARPES). This demonstrates how to circumvent the shortcomings of ARPES for investigation of magnetism involved with localized spins in limited size of two-dimensional crystals or multi-layer thin films that neutron scattering can hardly study due to lack of bulk compared to surface. Also, our observations give direct evidence for the spin ordering pattern of Cr(3+) ions in PdCrO2 suggested by neutron diffraction and quantum oscillation measurements, and provide a strong constraint that has to be satisfied by a microscopic mechanism for the unconventional anomalous Hall effect recently reported in this system.

SUBMITTER: Noh HJ

PROVIDER: S-EPMC3890906 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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