脉冲磁场对水热法制备Mn掺杂ZnO稀磁半导体的影响

本文以Zn(CH₃COO)₂·2H₂O, Mn(CH₃COO)₂·4H₂O和氨水缓冲溶液为原料, 在4 T脉冲磁场下利用水热法制备了Mn掺杂ZnO稀磁半导体晶体, 通过X射线衍射、 扫描电子显微镜、透射电子显微镜、拉曼光谱、荧光分光光度计及振动样品磁强计等对样品的微观结构及磁性能等进行了表征, 结果表明: Mn掺杂ZnO稀磁半导体晶体仍保持ZnO六方纤锌矿结构, 4 T脉冲磁场下合成的Mn掺杂ZnO稀磁半导体晶体具有明显的室温铁磁性, 其饱和磁化强度(M_s)为0.028 emu/g, 比无脉冲磁场下制备的样品提高一倍以上, 且4 T 脉冲磁场将样品的居里温度提高了15 K.

Effects of pulsed magnetic field on Mn-doped ZnO diluted magnetic semiconductor prepared by hydrothermal method

In this study, zinc acetate, manganese acetate, ammonium hydroxide and ammonium chloride are used as the source materials to prepare crystalline Mn-doped ZnO diluted magnetic semiconductor by hydrothermal method under a 4 T pulsed magnetic field. The microstructures, morphologies and magnetic properties of the samples are characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, Raman scattering spectra, Photoluminescnce and vibrating sample magnetometer. The effect of pulsed magnetic field on the microstructure and magnetic property of the Mn-doped ZnO diluted magnetic semiconductor are discussed. The result indicates that all the samples are still of hexagonal wurtzite structure. The pulsed magnetic field promotes the crystal growth, and improves room temperature ferromagnetism. The saturation magnetization (0.028 emu/g) of the sample fabricated under 4 T pulsed magnetic field is more than two times that of the sample synthesized without pulsed magnetic field. The Curie temperature (T_c) of the Mn-doped ZnO increases 15 K through the pulsed magnetic field processing.