W、Mo、Pt、Pd探针恒流、恒高模式STM图像比较研究

Comparative Studies on the Constant-height and Constant-current STM Images of W, Mo, Pt and Pd Tips

应用激子动力学方法 ,计算机模拟了 W、Mo、Pt、Pd探针恒流、恒高模式扫描隧道显微镜 (STM)图谱。结果显示出 ,不同探针恒流模式 STM图谱分辨率基本一致 ,而恒高模式的 STM图谱以 Pd探针分辨率较高 ,W、Mo探针次之 。

The constant height and constant current Scanning Tunneling Microscopy(STM) images of W, Mo, Pt and Pd tips were simulated respectively by the method of exciton dynamics. The results show that, for the constant current STM images, the spacial resolution is independent of the types of the tips' materials; but for the constant height STM images, the spacial resolution of the current densities is strongly dependent on the types of the tips' materials. The spacial resolution of the current density of the Pd tip is better than that of W and Mo tips, and the spacial resolution of the current density of the Pt tip is worse than that of W and Mo tips.