Comparison of AFM-IR and s-SNOM Technologies

This technical note compares two nanoscale infrared (IR) spectroscopy techniques: atomic force infrared microscopy (AFM-IR) and scattering-type scanning near-field optical microscopy (s-SNOM). It outlines the operational principles of both methods, emphasizing their capabilities in providing chemical specificity and nanoscale spatial resolution. The document details the unique benefits of each technique, particularly focusing on tapping AFM-IR and pseudoheterodyne s-SNOM, which are suitable for materials science applications in the mid-IR spectral range. The note also discusses the instrumentation involved, including the types of IR sources used and the importance of proper alignment and detection methods. Additionally, it highlights the advancements in s-SNOM, such as point spectroscopy, which enhances the speed and sensitivity of nanoscale IR imaging. The comparison includes a table summarizing the analytical capabilities, spatial resolution, and other critical parameters of both techniques, providing a comprehensive understanding of their applications in modern research.