Scanning Tunneling Microscopy and Ultralow Temperature Transport Measurements on Quench Condensed Films

本实验项目涉及低温扫描隧道显微镜和强无序超薄膜上的电子磁输运和隧道测量。这些实验将研究在二维强无序极限下电子系统中发生的深刻的、有时是惊人的变化（例如，超导体到绝缘体的转变）背后的物理效应。超薄金属薄膜是通过在接近4 K的温度下将组成金属热蒸发到衬底上来原位制备的。用扫描隧道显微镜进行的实验将测量原子表面结构及其局部隧道态密度的变化。从基本观点和技术观点来看，这些实验都很有趣，因为结果将增加我们对金属中电子传导过程的理解。本实验项目涉及低温扫描隧道显微镜和强无序超薄膜上的电子磁输运和隧道测量。这些实验将研究在二维强无序极限下电子系统中发生的深刻的、有时是惊人的变化（例如，超导体到绝缘体的转变）背后的物理效应。超薄金属薄膜是通过在接近4 K的温度下将组成金属热蒸发到衬底上来原位制备的。用扫描隧道显微镜进行的实验将测量原子表面结构及其局部隧道态密度的变化。从基本观点和技术观点来看，这些实验都很有趣，因为结果将增加我们对金属中电子传导过程的理解。＊＊＊

9502920 Valles This experimental project involves low temperature scanning tunneling microscopy and electron magneto-transport and tunneling measurements on strongly disordered ultrathin films. The experiments will investigate the physical effects behind the profound and sometimes spectacular changes (e.g.,the superconductor to insulator transition) that occur in electronic systems in the strongly disordered limit in two dimensions. The ultra-thin metal films are fabricated in situ by thermal evaporation of the constituent metals onto substrates held at temperatures near 4 K. Experiments with the scanning tunneling microscope will measure the atomic surface structure as well as variations in their local tunneling density of states. The experiments are of interest from fundamental viewpoints, as well as technical viewpoints, as the results will increase our understanding of electronic conduction processes in metals. %%% This experimental project involves low temperature scanning tunneling microscopy and electron magneto-transport and tunneling measurements on strongly disordered ultrathin films. The experiments will investigate the physical effects behind the profound and sometimes spectacular changes (e.g., the superconductor to insulator transition) that occur in electronic systems in the strongly disordered limit in two dimensions. The ultra-thin metal films are fabricated in situ by thermal evaporation of the constituent metals onto substrates held at temperatures near 4 K. Experiments with the scanning tunneling microscope will measure the atomic surface structure as well as variations in their local tunneling density of states. The experiments are of interest from fundamental viewpoints, as well as technical viewpoints, as the results will increase our understanding of electronic conduction processes in metals. ***