and electrons tunnel from the occupied states of the tip into the empty states of the sample (Figure 1(b)). Figure 1. Basic principles of STM and STS. (a) Schematic representation of STM. A voltage V ...

For maximum resolution in a scanning tunneling microscope (STM), an extremely sharp metallic tip is required, which serves as the point through which the STM “scans” a sample. A blunt tip reduces STM ...