Division of Superconductivity and Magnetism, Faculty of Physics and Geosciences, University of Leipzig, Leipzig, Germany.
J Phys Condens Matter. 2012 Feb 29;24(8):086007. doi: 10.1088/0953-8984/24/8/086007.
The electric polarization, dielectric permittivity, magnetoelectric effect, heat capacity, magnetization and ac susceptibility of magnetite films and polycrystals were investigated. The electric polarization of magnetite films with saturation values between 4 and 8 μC cm(-2) was found to vanish between 32 and 38 K, but in polycrystals no phase transition was detected in this range by heat capacity. Both types of samples showed magnetoelectric effects at low temperatures below a frequency-dependent crossover. This is interpreted as arising from multiferroic relaxor behavior.
研究了磁铁矿薄膜和多晶的极化强度、介电常数、磁电效应、热容、磁化强度和交流磁化率。发现饱和值在 4 到 8 μC cm(-2)之间的磁铁矿薄膜的极化强度在 32 到 38 K 之间消失，但在多晶中，热容在这个范围内没有检测到相变。这两种类型的样品在低于频率相关交叉点的低温下都表现出磁电效应。这被解释为源于多铁弛豫行为。
