Magnetic and Structural Properties of Sr-Doped Ba$_{2-x}$Sr$_{x}$CoO$_{4}$

ORAL

Abstract

We have studied the structural and magnetic properties of a newly synthesized compound Ba$_{2-x}$Sr$_{x}$CoO$_{4}$ with different doping ($x)$ levels. Monoclinic Ba$_{2}$CoO$_{4}$ is an antiferromagnetic (AFM) insulator with N\'eel temperature $T_{N}$ = 25 K and a two-dimensional character with spins aligned in the \textit{ac} plane. The isovalent Sr doping causes changes in both crystal structure and magnetic properties. 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 crystal structure and physical properties will be discussed.

*Supported by NSF-DMR0346826, and DOE DE-FG02-04ER46125

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Authors

  • Hao Sha

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

  • Jiandi Zhang

    • Department of Physics, Florida International University, Miami, FL 33199
    • Florida International University, Miami, FL 33199
    • Florida International University
    • Florida International University (FIU), Miami, FL 33199

  • Qingzhen Huang

    • NIST Center for Neutron Research
    • NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899
    • National Institute of Standards and Technology (NCNR)

  • Ovidiu Garlea

    • Neutron Scattering Science Division, ORNL, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • Oak Ridge national laboratory
    • Oak Ridge National Laboratory

  • B.C. Sales

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

  • David Mandrus

    • Materials Science and Technology Division, ORNL, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Oak Ridge TN 37831
    • Oak Ridge Natl Lab

  • Ronying Jin

    • Materials Science and Technology Division, ORNL, Oak Ridge, TN 37831 and Univ. of Tennessee, Knoxville, TN 37996
    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory, Oak Ridge TN 37831
    • Oak Ridge National Laboratory