Heisenberg Model Analysis on Inelastic Powder Neutron Scattering Data Using Pure and K doped BaMn2As2 samples

ORAL

Abstract

Low temperature powder inelastic neutron scattering measurements (INS) were performed on powders of Ba(1-x)KxMn2As2 with x=0(BMA),0.125 and 0.25. BMA is a G type antiferromagnet (AFM) which has local magnetic modulations bridging between the pnictide and cuprate superconductors. Hole doping (K) introduces more metallic behavior. The magnetic contribution to the intensities were retrieved by subtracting the estimated phonon background obtained at high momentum transfers from the raw. The resultant estimated magnetic intensities were analyzed by using damped harmonic oscillator model. The K doping effects create a broadening in the magnetic peak profiles consistent with expected weak FM fluctuations. We also analyzed the INS data using a powder integration routine which is based on J1-J2-Jz Heisenberg Model. The Monte Carlo integration technique is used to obtain the powder-averaged S(Q,E) for a series of Js. The representative values (with lowest chi-squared) obtained for BMA are in agreement with previous results. The values obtained for K doped samples were found in the close proximity to the parent ones. Overall we conclude that the original AFM structure seen in BMA retained its character even in the K doped samples with minimal differences.

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Authors

  • Mehmet Ramazanoglu

    Istanbul Techinal Univiversity

  • A. Sapkota

    Ames Lab., Dept. of Physics and Astronomy, Iowa State Univ., Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Lab. & Iowa State Univ., Ames, IA, 50011

  • A. Pandey

    Ames Lab., Dept. of Physics and Astronomy, Iowa State Univ., Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Laboratory, Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Ames Lab. & Iowa State Univ., Ames, IA, 50011

  • David C. Johnston

    Ames Lab., Dept. of Physics and Astronomy, Iowa State Univ., Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Laboratory, Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Ames Lab. & Iowa State Univ., Ames, IA, 50011, Iowa State Univ, Ames Laboratory, Dept. of Phys. and Astro, Iowa State Univ.

  • Alan Goldman

    Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA, Ames Lab., Dept. of Physics and Astronomy, Iowa State Univ., Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Lab. & Iowa State Univ., Ames, IA, 50011, Iowa State University

  • A. Kreyssig$^{*}$

    Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA, Ames Lab., Dept. of Physics and Astronomy, Iowa State Univ., Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Lab. & Iowa State Univ., Ames, IA, 50011, $^*$Ames Laboratory, Dept. of Phys. and Astro., Iowa State University, IA, USA; $^+$University of Missouri Research Reactor, MO, USA

  • Douglas Abernathy

    Oak Ridge National Laboratory, Oak Ridge NAtional Lab., TN, 37831

  • Jennifer L. Niedziela

    Oak Ridge National Laboratory, Oak Ridge NAtional Lab., TN, 37831, Oak Ridge National Laboratory, Materials Science Division

  • Matthew Stone

    Oak Ridge NAtional Lab., TN, 37831, Quantum Condensed Matter Division, Oak Ridge National Laboratories, Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory, Spallation Neutron Source, Oak Ridge National Laboratory

  • R.J. McQueeney

    Ames Laboratory, Dept. of Physics and Astronomy, Iowa State University, Ames Lab. & Iowa State Univ., Ames, IA, 50011