Magnetization and magneto-transport staircaselike behavior in layered perovskite Sr(2)CoO(4) at low temperature

Polycrystalline layered perovskite Sr(2)CoO(4) sample was synthesized by high temperature and high pressure method. The staircaselike behavior has been observed in the magnetization and resistivity versus field curves of Sr(2)CoO(4) at low temperature. The main features of the steps can be obtained from the measured results: (i) the positions of the external magnetic field at which steps occur are varying in different measurement runs, (ii) the steps only appear at low temperature and disappear with a slight increase of the temperature, (iii) the steps are dependent on the temperature and field sweep rate. Based on the features of the magnetization and magneto-transport staircaselike behavior in Sr(2)CoO(4), the unusual phenomenon can be ascribed to an avalanche of flipping domains in terms of the random field theory.