Tuning Physical Properties via Isovalent Doping in Ba$_{2-x}$Sr$_{x}$CoO$_{4}$

ORAL

Abstract

It is known that monoclinic Ba$_{2}$CoO$_{4}$ is an antiferromagnetic (AFM) insulator with Neel temperature $T_{N}$=25K. We found that isovalent Sr substitution for Ba drastically changes the structural and magnetic properties of Ba$_{2-x}$Sr$_{x}$CoO$_{4}$ system. With increasing $x$, $T_{N}$ initially increases then decreases after reaching the maximum at $x$=0.5. Correspondingly, its crystal structure changes from monoclinic ($x<$0.5) to orthorhombic ($x\ge $0.5) at room temperature. The correlation between structure and physical properties will be discussed.

*The work was partially supported by NSF-DMR0453804, NSF-DMR0346826, DE-FG02-05ER46202, and DOE DE-FG02-04ER46125. Research Sponsored by the Division of Materials Sciences and Engineering, BES, U.S. DOE, under contract DE-AC05-00OR22725 with ORNL.

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Authors

  • Hao Sha

    • Department of Physics, Florida International University, Miami, FL 33199

  • Jiandi Zhang

    • Florida International University
    • Department of Physics, Florida International University, Miami, FL 33199

  • Q. Huang

    • NIST Center for Neutron Research
    • NIST Center for Neutron Research, Gaithersburg, Maryland 20899

  • V.O. Garlea

    • Oak Ridge National Laboratory
    • ORNL
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831

  • Brian Sales

    • Oak Ridge National Laboratory, Oak Ridge TN 37831
    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
    • Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831

  • David Mandrus

    • Oak Ridge National Laboratory, Oak Ridge TN 37831
    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
    • Oak Ridge National Laboratory
    • Oak Ridge National Lab., Materials Science and Technology Division, Oak Ridge, TN
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831

  • Rongyin Jin

    • ORNL
    • Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831