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arXiv · cond-mat/0507546

Observation of oscillatory magnetoresistance periodic in 1/B and B in Ca3Ru2O7

Abstract

We report magnetoresistance oscillations in high magnetic fields, B, up to 45 T and over a wide range of temperature in the Mott-like system Ca3Ru2O7. For B rotating within the ac-plane, slow and strong Shubnikov-de Haas (SdH) oscillations periodic in 1/B are observed for T≤1.5 K in the presence of metamagnetism. These oscillations are highly angular dependent and intimately correlated with the spin-polarization of the ferromagnetic state. For B||[110], oscillations are also observed but periodic in B (rather than 1/B) which persist up to 15 K. While the SdH oscillations are a manifestation of the presence of small Fermi surface (FS) pockets in the Mott-like system, the B-periodic oscillations, an exotic quantum phenomenon, may be a result of anomalous coupling of the magnetic field to the t2g-orbitals that makes the extremal cross-section of the FS field-dependent.

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V. Durairaj, X. N. Lin, Z. X. Zhou, S. Chikara, E. Ehami, A. Douglass, P. Schlottmann, G. Cao. 2005-07-22. Observation of oscillatory magnetoresistance periodic in 1/B and B in Ca3Ru2O7. https://doi.org/10.1103/physrevb.73.054434

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