Session J33: Focus Session: Dielectric, Ferroelectric, and Piezoelectric Oxides: Multiferroics & Magnetoelectrics II

11:15 AM–2:15 PM, Tuesday, March 22, 2011
Room: C143/149

Sponsoring Units: DMP DCOMP
Chair: Craig Fennie, Cornell University

Abstract ID: BAPS.2011.MAR.J33.2

Abstract: J33.00002 : Giant Magnetoelectric Effect in Antiferromagnetic BaMnO$_{3-\delta}$ and Its Derivatives

11:27 AM–11:39 AM

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Authors:

  M. Ge
    (University of Kentucky)

  O.B. Korneta
    (University of Kentucky)

  T.F. Qi
    (University of Kentucky)

  S. Parkin
    (University of Kentucky)

  L.E. DeLong
    (University of Kentucky)

  G. Cao
    (University of Kentucky)

  P. Schlottmann
    (Florida State University)

Hexagonal perovskite 15R-BaMnO$_{2.99}$ with a ratio of cubic to hexagonal layers of 1/5 in the unit cell is an antiferromagnetic insulator that orders at a N\'eel temperature T$_{N }$= 220 K. Here we report structural, magnetic, dielectric and thermal properties of single crystal BaMnO$_{2.99}$ and its derivatives BaMn$_{0.97}$Li$_{0.03}$O$_{3}$ and Ba$_{0.97}$K$_{0.03}$MnO$_{3}$. The central findings of this work are: \textbf{(1)} these materials possess a usually large, high-temperature magnetoelectric effect that amplifies the dielectric constant by more than an order of magnitude near their respective N\'eel temperature; \textbf{(2)} Li and K doping can readily vary the ratio of cubic to hexagonal layers and cause drastic changes in dielectric and magnetic properties. These findings provide a new paradigm for developing \textit{novel}, \textit{high-temperature magnetoelectric} \textit{materials} that may eventually contribute to technology.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2011.MAR.J33.2