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利用混合物理化学气相沉积法在石墨衬底上制备出了晶形为六角结构、厚度不同、径向尺寸不一的Mg B2单晶纳米晶片.利用纳米定向转移技术将此晶片转移到了碳支持膜铜网上,以便对其精细结构等物性进行表征.电输运测量和磁性测量结果都表明晶片具有超导电性:T c onset=38K,T c(0)=33K.扫描电子显微镜图像表明,晶片表面平整、厚度分布在几个纳米到200 nm之间,宽度从几微米到上百微米;高分辨透射电镜图像显示出晶片具有周期性晶格条纹.选区电子衍射数据与Mg B2已有的单晶衍射数据相符.这些测量结果证实了其确为高质量单晶Mg B2超导纳米晶片.本文不仅提出了一种全新的制备单晶Mg B2的方法,也观察到了纳米尺度Mg B2单晶的零电阻现象,为后续的磁通钉扎、纳米力学性能等领域的深入研究提供了合适的素材.
MgB2 single crystal nanocrystalline wafers with hexagonal crystal structure, different thickness and different radial size were prepared on graphite substrate by mixed physical and chemical vapor deposition method.The nanocrystal was transferred to carbon supporting carbon network by nano-directional transfer technology In order to characterize the physical properties such as its fine structure, etc. Both the electrical transport measurements and the magnetic measurements show that the wafer has superconductivity: T c onset = 38 K, T c (0) = 33 K. Scanning electron microscopy images show that the wafer surface is flat , The thickness of the distribution in a few nanometers to 200 nm, width from a few microns to hundreds of microns; high-resolution transmission electron microscopy images show that the wafer has periodic lattice fringes. Selected electron diffraction data and Mg B2 existing single crystal diffraction These measurements confirm that it is indeed a high quality single crystalline Mg B2 superconducting nanocrystalline wafer.In this paper, not only a new method of preparing single crystal Mg B2, but also observed the zero resistance of nanoscale Mg B2 single crystal Phenomenon for the follow-up flux pinning, nanomechanical properties and other areas in-depth study provides the appropriate material.