Heinrich Rohrer

Heinrich Rohrer co-invented the scanning tunneling microscope (STM) with Gerd Binnig at IBM's Zurich Research Laboratory in 1981. The STM was the first instrument capable of imaging individual atoms on a surface, revolutionizing nanotechnology and surface science.

Rohrer shared the 1986 Nobel Prize in Physics with Gerd Binnig for their work on the STM, and the prize was also shared with Ernst Ruska for his earlier invention of the electron microscope. The Nobel committee recognized that the STM had opened an entirely new field of microscopy.

Rohrer worked at the IBM Zurich Research Laboratory in Rüschlikon, Switzerland, where he spent his entire research career. It was there that he collaborated with Binnig to develop the scanning tunneling microscope.

The STM is used to image and manipulate individual atoms and molecules on conducting or semiconducting surfaces. It works by measuring quantum tunneling current between a sharp metallic tip and the surface, allowing scientists to create atomic-resolution topographic maps of materials.

An STM uses an extremely sharp metal tip positioned just a few angstroms above a sample surface. When a voltage is applied, electrons 'tunnel' across the gap between the tip and the surface, and the resulting current is so sensitive to distance that variations of less than the diameter of a single atom can be detected and mapped.