Magnetic properties in the Mott-insulating iron oxychalcogenides La$_{2}$O$_{2}$Fe$_{2}$OSe$_{2}$

ORAL

Abstract

The role of electron correlation and magnetism in high-temperature superconductivity of the iron pnictides has been a topic of discussion. It has also motivated interest to compare related compounds with the iron pnictides and chalcogenides. Recently both electronic structure calculations and experimental measurements have indicated that the iron oxychalcogenides La$_{2}$O$_{2}$Fe$_{2}$OSe$_{2}$, which contains an Fe square lattice with an enlarged unit cell, has a larger U/t and is a Mott insulator [1]. We focus here on the understanding of the magnetism of this system. Within the density functional theory, we consider the magnetic phase diagram. Using an effective frustrating spin-exchange model in a doubled checker-board lattice, we study the magnetic excitation spectrum. Our theoretical results are compared with the emerging elastic and inelastic neutron scattering data in this compound. \\[4pt] [1] J.-X. Zhu, R. Yu \textit{et. al}, Phys. Rev. Lett. \textbf{104}, 216405 (2010).

*This work was supported by the NNSA of the U.S. DOE at LANL under Contract No. DE-AC52-06NA25396 (J.X.Z), the NSF Grant No. DMR-0706625, the Robert A. Welch Foundation Grant No. C-1411, and the W. M. Keck Foundation (R.Y. and Q.S.).

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Authors

  • Jian-Xin Zhu

    • Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
    • Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
    • Los Alamos National Lab, Theoretical Division
    • Los Alamos National Laboratory, Los Alamos, NM 87545
    • Theoretical Division, Los Alamos National Laboratory
    • Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545
    • Los Alamos National Laboratory

  • Rong Yu

    • Rice University
    • Rice Univ.
    • Department of Physics \& Astronomy, Rice University, Houston, TX 77005

  • Qimiao Si

    • Rice University
    • Department of Physics and Astronomy, Rice University
    • Department of Physics \& Astronomy, Rice University, Houston, TX 77005