Structural, magnetic, and electronic transport properties of (Sr0.9Ca0.1)3Ru2O7 single crystal

Bin Qian
Zhe Qu
Jin Pen
Tijiang Liu
Xiaoshan Wu
L Spinu, University of New Orleans
Z Q. Mao

Abstract

We have studied the structural, magnetic, and electronic transport properties of (Sr_0.9Ca_0.1)₃Ru₂O₇ using single crystals grown by a floating-zone technique. The structure analysis by Rietveld refinements reveals that the Ca substitution for Sr intensifies the structure distortion; the rotation angle of the RuO₆ octahedron increases. This structure change tunes magnetic and transport properties dramatically. The magnetic ground state switches from an itinerant metamagnetic state for Sr₃Ru₂O₇ to a nearly ferromagnetic state for (Sr_0.9Ca_0.1)₃Ru₂O₇. The Fermi liquid behavior occurs in Sr₃Ru₂O₇, but is suppressed in (Sr_0.9Ca_0.1)₃Ru₂O₇. These results strongly suggest that lattice, spin, and charge degrees of freedom are strongly coupled in this system. The band width narrowing caused by the structure distortion should be responsible for the enhancement of ferromagnetic correlations and the change of transport properties.