Real-space magnetic imaging of the spinel MnV2O4

Spinel;Spinels;Multiferroic;multiferroics;multiferroism;Magnetic force microscopy (MFM);MnV2O4;Magnetic imaging;Strain;Quantitative magnetic force microscopy (MFM)

Wolin, Brian Augustus

关键词: Spinel;    Spinels;    Multiferroic;    multiferroics;    multiferroism;    Magnetic force microscopy (MFM);    MnV2O4;    Magnetic imaging;    Strain;    Quantitative magnetic force microscopy (MFM);   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/98089/WOLIN-DISSERTATION-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Controlling multiferroic behavior in materials will enable the development of a wide variety of technological applications. However, the exact mechanisms by which multiferroic behavior arises in many materials are not well understood. One such class of materials are the spinels, including MnV2O4.Bulk probe studies of this compound have yielded conflicting and inconclusive results. To inform the debate and better understand the underlying physics, we performed magnetic force microscopy measurements on two MnV2O4 samples with differing degrees of mechanical strain. These local investigations revealed sub-um-scale patterns in the magnetic structure in both samples. In one case, the magnetization of these stripes is estimated at Mz ~ 10^5 A/m, which is on the order of previous saturation magnetization measurements.The discovery of such large inhomogeneities necessitates revision of theoretical proposals and reinterpretation of experimental data regarding the low-temperature phases of the spinels. Similar MFM measurements of a related material (Mn3O4) provide evidence that magnetic inhomogeneity is a common feature in the magnetically ordered phases of multiferroic spinel compounds.