【摘要】 界面与尺度效应会影响材料的压致结构相转变和电输运特性.通过化学合成方法可以获得不同尺寸的材料,它们具有不同的压致结构相转变和电输运特性.与化学合成方法不同,物理研磨方法得到的小尺寸材料会有更多的表面缺陷,导致材料表面能和内聚能的不同,它们在压力作用下的结构和电输运特性未知.本文以ZnTe样品为例,利用高压原位交流阻抗谱和直流电阻率测量方法对利用物理研磨方法得到的晶粒尺寸分别为170nm和410nm的样品进行了测量,实验最大压力为20GPa.结果分析发现:物理研磨得到的ZnTe样品的尺寸和界面效应对其压致相转变压力和宏观电输运性质均有显著的影响.更多还原

【Abstract】 Interface and scale effects can affect both the structural phase transitions and the electrical transportation properties of materials. Materials with different size can be obtained by chemical synthesis. They have different pressure-induced structural phase transitions and electrical transport properties under compression. Different from chemical synthesis methods,the small scale material obtained by physical grinding method will have more surface and interface defects,resulting in different material surface energy and intrinsic energy,their structure and electrical transportation properties are unknown under pressure. In this paper,using high pressure in situ alternating current impedance spectrum and direct current resistivity measurements,170 nm and 410 nm sized Zn Se particles were obtained by physical grinding. The maximum pressure was 20 GPa. It was found that the size and interface effect of ZnTe sample obtained by physical grinding has a significant influence on the pressure-induced phase transformation pressure and electrical transportation properties.更多还原