Anomalous Hall Resistivity of TbBaCo2O5.53 with Nontrivial Magnetic Structure

To investigate the Hall resistivity ρ H of systems with nontrivial spin structures, the transport and magnetic properties of the oxygen-deficient perovskite system TbBaCo 2 O 5.53 with nontrivial magnetic structures have been studied. As is already known, the system exhibits, with decreasing temperature T , a transition to a ferromagnetic (FM) phase with a noncollinear magnetic structure at T C ∼280 K in zero magnetic field, and with further decreasing T , the spontaneous magnetization begins to decrease at T 1 ∼260 K and becomes zero at T N ∼245 K, where an antiferromagnetic (AFM) phase with a noncollinear magnetic structure is realized. The metamagnetic behavior is induced by a relatively small magnetic field H (<5 T) in the T -region between ∼200 K and T 1 . In this T -region, unusual H -dependence of ρ H has been observed. By analyzing the observed ρ H and magnetization M , the H -dependence of the anomalous Hall coefficient R s has been obtained at various fixed temperatures. On the basis of the magn...