The spin-orbit Mott state in the novel quasi-2D iridate Ba 2IrO4 was studied on crystal structure, electrical resistivity, magnetic susceptibility, and μSR experiments. Ba 2IrO4 crystallizes in a K2NiF4-type structure (I4/mmm, a = 4.030(1) Å and c = 13.333(4) Å) which includes IrO2 square planer lattices with straight Ir-O-Ir bonds. The minimal Mott-gap size is ∼70 meV The magnetic ground state is antiferromagnetic long-range order (TN ∼ 240 K) without spin canting. The magnetic moment (|μ| ∼ 0.34 μB/Ir) is much reduced by a low-dimensional quantum spin fluctuation with a large intra-plane correlation |J|. The critical exponent (β ∼ 0.18) suggests that the magnetic state is classified into 2-D X-Y or (anisotropic) Heisenberg spin systems with weak 3-D interlayer coupling |J'|.
|Journal||Journal of Physics: Conference Series|
|Issue number||PART 3|
|Publication status||Published - Jan 1 2012|
|Event||26th International Conference on Low Temperature Physics, LT 2011 - Beijing, China|
Duration: Aug 10 2011 → Aug 17 2011
ASJC Scopus subject areas
- Physics and Astronomy(all)