Investigation of multiferroic magnetic systems by ultrasonic velocity measurements

我们主要对同时具有反铁磁性、铁电性和铁弹性的多铁化合物的研究感兴趣。除了基本的科学兴趣之外，这类磁电材料（显示其磁性和铁电性质之间耦合的材料）可能被用作未来电子存储设备中控制磁化的替代手段，以及致动器，开关和磁场传感器。对这一领域的兴趣是由最近的结果引发的，这些结果表明三角形晶格反铁磁体，由于磁挫折而有利于非共线自旋构型，是观察强磁电效应的良好候选者。因此，本研究计划的目的是研究在CuO （T = 230 K）和BiFeO3 （T = 643 K）的低温甚至高温下螺旋磁结构稳定后显示铁电性的一系列受挫多铁化合物的磁性、铁电性和弹性。

We are principally interested in the study of multiferroic compounds which are simultaneously antiferromagnetic, ferroelectric, and ferroelastic. Besides the fundamental scientific interest, this class of magnetoelectric materials (materials that show a coupling between their magnetic and ferroelectric properties) can potentially be used as an alternative means for controlling the magnetization in future electronic memory devices, as well as for actuators, switches, and magnetic field sensors. The interest in this field has been trigger by recent results which suggest that triangular lattice antiferromagnets, which favour non-collinear spin configuration due to magnetic frustration, are good candidates for the observation of strong magnetoelectric effects. Thus, the objective of this program of research is to investigate the magnetic, ferroelectric, and elastic properties of a series of frustrated multiferroic compounds which display ferroelectricity induced upon the stabilization of a helical magnetic structure at low or even high temperatures in the case of CuO (T = 230 K) and BiFeO3 (T = 643 K).