Unconventional magnetic properties of the weakly ferromagnetic metal BaIrO_3

Abstract

We present experimental evidence for small-moment magnetism below the ferromagnetic transition temperature (T_c3 = 183 K) in the quasi-one-dimensional metal BaIrO_3. Further, we identify rearrangement of the local magnetic moment distribution, which leaves the bulk magnetization unchanged, at the Mott-like transition (T_c1 = 26 K). These results are only possible via muon-spin relaxation ($\hat{I}¼$SR) techniques, since neutron scattering studies are hindered by the large absorption of neutrons by Ir. The low temperature characteristics of this compound, as revealed by $\hat{I}¼$SR, are unconventional, and suggest that its magnetic properties are driven by changes occuring at the Fermi surface due to the formation of a charge-density wave state.

4 pages, 4 figures