Use of optical methods for studying photocurrent generation mechanism in silver nanowires and defects in glass

The light-matter interaction covers a wide range of physical phenomena which can be used for the investigation of materials. This interaction can be used both spectroscopically and microscopically to investigate fundamental material properties such as structural, optical, and electrical properties. In this thesis, I used optical methods to characterize materials on macro and nanoscales based on different light phenomena such as scattering, transmission, absorption, and re-flection. First, I used Raman spectroscopy in a diffraction-limited setup to show that the trapped gas inside the bubble defects can be identified in a matter of seconds non-destructively. Also, I investigated near-field methods to gain further understanding about chemical, optical and structural information in nanomate-rials by using an aperture-based transmission mode Near-field Scanning Optical Microscopy (SNOM). Finally, I used scanning photocurrent microscopy to demon-strate photocurrent generation in silver nanowires and nanowire networks. This thesis demonstrates that light-matter interaction can provide useful information in the characterization of a vast class of materials. The advantages of the non-destructive Raman technique in defects analyses, the challenges of working in the near-field region in nanomaterials characterization, and also the photocurrent generation in silver nanowires for the first time have been demonstrated with experimental results.