Scanning near-field optical microscopy methods for studies of chemistry and materials approaching the atomic scale

摘要: The convergence of optical spectroscopy with scanning probe microscopy (SPM) provides a near-field sensitive platform that circumvents the limitations of light diffraction and can measure highly localized heterogeneity and phenomena. In ultrahigh vacuum (UHV) and at cryogenic temperatures the spatial resolution of these methods can be pushed towards the atomic scale. Here, efforts to use UHV scanning tunneling microscopy (STM) coupled with tip-enhanced Raman spectroscopy (TERS) to investigate the behavior and chemistry of molecular adsorbates on pristine and modified noble metal substrates are highlighted. Spectroscopic imaging provides the ability to visualize highly localized phenomena, while vibrational fingerprints derived from light-matter interactions can be used to understand their effects on a molecule’s or material’s structure. This can provide insight into adsorbate-substrate interactions …