Dielectric and magnetic properties of the multiferroic Tb(1−x)BixMnO3: Electric dipole glass and self-organization of charge carriers

Abstract

Single crystals of the new multiferroic Tb(1−x)BixMnO3 have been grown and studied. A semiconductor compound with x = 0.05 is investigated in most detail. At temperatures T ≥ 165 K, the electric dipole glass state is realized in the crystal. Localized charge carriers form conducting drops of electrons and holes, which are located predominantly in thin layers at the boundaries of polar domains. When drops escape as the temperature increases, jumps in conductance and capacitance are observed. The state of drops is controlled by low bias voltage. The long-range magnetic order arises at temperatures T ≤ 90 K. Negative magnetoresistance is observed at temperatures of the existence of localized charge carriers.