A layered iridate Ba2IrO4 was synthesized using a high-pressure synthesis technique. Its electronic state was studied through electrical resistivity, magnetic susceptibility, and μSR experiments. It was found that Ba2IrO4 crystallizes in a K2NiF 4-type structure (space group I4/mmm) with lattice parameters a =4.030(1) and c =13.333(4). The structure includes flat IrO2 square planar lattices with straight Ir-O-Ir bonds. Ba2IrO4 is a Mott insulator (activation energy ΔEa ∼ 0.07 eV) driven by a spin-orbit interaction. The magnetic susceptibility and μSR studies revealed that the magnetic ground state is antiferromagnetic long-range order (TN ∼ 240 K) in which the magnetic moment (∼0. 34μB/Ir atom) is significantly reduced by a low-dimensional quantum spin fluctuation with a large intraplane correlation |J|. The behavior is similar to that in parent materials of high-TC cuprate superconductors such as La2CuO4.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Apr 20 2011|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics