Electrical Resistance of a Monatomic Step on a Crystal Surface

Abstract

We have succeeded in measuring the resistance across a single atomic step through a monatomic-layer metal on a crystal surface, Si(111)(sqrt[3]xsqrt[3])-Ag, using three independent methods, which yielded consistent values of the resistance. Two of the methods were direct measurements with monolithic microscopic four-point probes and four-tip scanning tunneling microscope probes. The third method was the analysis of electron standing waves near step edges, combined with the Landauer formula for 2D conductors. The conductivity across a monatomic step was determined to be about 5 x 10(3) Omega(-1) m(-1). Electron transport across an atomic step is modeled as a tunneling process through an energy-barrier height approximately equal to the work function.

Interwire coupling forIn(4×1)/Si(111) probed by surface transport

“…From potentiometry and transport measurements, it is known that monatomic steps significantly increase the resistance [25][26][27], and thus the vicinality of the Si(111) surface should have an effect on the In/Si(111) anisotropy.…”

Impact of Surface Conditions on the Superconductivity of Si(111)-(√7 × √3)-In

“…Shortly after the first observation of superconducting energy gap by means of scanning tunneling spectroscopy (STS) [1], insitu electrical transport measurements have demonstrated that supercurrents can travel over macroscopic distances in those surface systems [2][3][4]. The finding of the macroscopic supercurrents was unexpected, because the surfaces always have atomic steps that may decouple metallic films grown on the terraces [6,7]. The temperature dependence of the critical current suggests that the supercurrents flow across the atomic steps with the help of the Josephson effect [2].…”

Imaging Josephson Vortices on the Surface SuperconductorSi(111)−(7×3)Yoshizawa1, Kim2, Kawakami3 et al. 2014Phys. Rev. Lett.753570View full textAdd to dashboardCite

“…Atomic steps are considered to strongly affect electron transport phenomena, because they potentially decouple neighboring surface terraces [12][13][14][15]. This could prevent superconducting currents from running over a long distance.…”