Scanning tunneling microscope

A scanning tunneling microscope (STM) is a high-precision instrument used to visualize surfaces at the atomic level. It works by bringing a sharp metal tip very close to the material's surface. When a voltage is applied, electrons "tunnel" between the tip and the surface, creating a tiny current. This current varies depending on the distance and the surface's atomic structure. By scanning the tip across the surface and monitoring the current, the STM constructs detailed images of individual atoms and molecules, providing insight into material properties at an incredibly small scale.