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Field-tuned Collapse of an Orbital Ordered and Spin-polarized State: Colossal Magnetoresistance in Bilayered Ruthenate

G. Cao·L. Balicas·X. N. Lin·S. Chikara·V. Duairaj·E. Elhami·J. W. Brill·R. C. Rai
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Abstract

Ca3Ru2O7 with a Mott-like transition at 48 K features different in-plane anisotropies of magnetization and magnetoresistance. Applying magnetic field along the magnetic easy-axis precipitates a spin-polarized state via a first-order metamagnetic transition, but does not lead to a full suppression of the Mott state, whereas applying magnetic field along the magnetic hard axis does, causing a resistivity reduction of three orders of magnitude. The colossal magnetoresistivity is attributed to the collapse of the orbital ordered and spin-polarized state. Evidence for a density wave is also presented.

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G. Cao, L. Balicas, X. N. Lin, S. Chikara, V. Duairaj, E. Elhami, J. W. Brill, R. C. Rai. 2003-07-03. Field-tuned Collapse of an Orbital Ordered and Spin-polarized State: Colossal Magnetoresistance in Bilayered Ruthenate. https://doi.org/10.1103/physrevb.69.014404

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