In situ plasmonic tip preparation and validation techniques for scanning tunneling microscopy

Abstract

Among the many parts constituting a scanning tunneling microscope, the metallic tip is the component that directly interacts with the specimen and plays a critical role in visualizing the physical quantity of interest. While tip materials such as W and Pt–Ir are commonly used for topographic imaging and their preparation is well-documented, the preparation of plasmonic materials such as Ag for tip-enhanced Raman spectroscopy is relatively less standardized. Here, we present several in situ Ag tip preparation and validation techniques for the microscopist to use depending on their intended application, including atomic resolution imaging, scanning tunneling spectroscopy (STM), and tip-enhanced Raman spectro-microscopy in ultrahigh vacuum. Besides optical applications, these methods are not limited to Ag but also applicable to other STM tip materials.

Modulation of Carbon Nanotube Electronic Structure by Grain Boundary Defects in RbI on Au(111)

“…Experiments were carried out in a home-built ultrahigh vacuum (UHV) cryogenic STM system, where the bias voltage (V b ) is applied to the sample . All imaging and spectroscopic measurements were carried out at 26 K using electrochemically etched silver tips . A Au(111)/mica substrate was prepared in situ by using multiple neon sputtering/annealing cycles.…”

In situ and ex situ approaches for molecular scale understanding of electrochemical interfaces

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