Influence of atomic tip structure on the intensity of inelastic tunneling spectroscopy data analyzed by combined scanning tunneling spectroscopy, force microscopy and density functional theory

Abstract

Achieving a high intensity in inelastic scanning tunneling spectroscopy (IETS) is important for precise measurements. The intensity of the IETS signal can vary up to a factor three for various tips without an apparent reason accessible by scanning tunneling microscopy (STM) alone. Here, we show that combining STM and IETS with atomic force microscopy enables carbon monoxide front atom identification, revealing that high IETS intensities for CO/Cu(111) are obtained for single atom tips, while the intensity drops sharply for multi-atom tips. Adsorbing the CO molecule on a Cu adatom [CO/Cu/Cu(111)] such that it is elevated over the substrate strongly diminishes the tip dependence of IETS intensity, showing that an elevated position channels most of the tunneling current through the CO molecule even for multi-atom tips, while a large fraction of the tunneling current bypasses the CO molecule in the case of CO/Cu(111).

References in corpus (7)

• Inelastic transport theory from first-principles: methodology and applications for nanoscale devices
• The origin of high-resolution IETS-STM images of organic molecules with functionalized tips
• Unified description of inelastic propensity rules for electron transport through nanoscale junctions
• CO Tip Functionalization Inverts Atomic Force Microscopy Contrast via Short-Range Electrostatic Forces
• Simulation of inelastic electron tunneling spectroscopy of single molecules with functionalized tips
• Chemical and Crystallographic Characterization of the Tip Apex in Scanning Probe Microscopy
• Scanning tunneling microscopy current from localized basis orbital density functional theory

Cited by in corpus (6)

• Submolecular resolution by variation of IETS amplitude and its relation to AFM/STM signal
• Analysis of STM images with pure and CO-functionalized tips: A first-principles and experimental study
• Atomic Force Extrema Induced by the Bending of a CO-Functionalized Probe
• Scanning tunneling microscopy using CO-terminated probes with tilted and straight geometries
• STM contrast of a CO dimer on a Cu(1 1 1) surface: a wave-function analysis
• Selective resolution of phonon modes in STM-IETS on clean and oxygen-adsorbed Cu(100) surfaces