Gerd Karl Binnig, born in 1947, German physicist and Nobel Prize winner. He invented, with colleague Swiss physicist Heinrich Rohrer, the scanning tunneling microscope (STM), a new type of powerful microscope capable of detecting images at the atomic level. For this accomplishment, they shared the 1986 Nobel Prize in physics with German physicist Ernst August Friedrich Ruska, who was honored for his invention of the electron microscope.

Born in Frankfurt, Binnig was educated in that city at the J. W. Goethe University, where he earned his Ph.D. degree in 1978. He joined the International Business Machines (IBM) Research Laboratory near Zürich, Switzerland, that same year, and began working with Rohrer on a problem that required information on a microscopically small surface. They developed the idea of a probe that could move across an object's surface to obtain this information. The ultimate result was the creation of the scanning tunneling microscope.

The STM that Binnig and Rohrer invented is based on the wavelike property of electrons, first identified in the 1920s by Nobel laureate Louis Victor de Broglie. The microscope's sharp probe moves near the sample's surface, and any change in distance between the probe and the sample—even as small as the diameter of a single atom—is recorded by the microscope. By moving the probe in a sweeping motion, a three-dimensional image can be produced. This image shows detail not possible with any other kind of microscope. It can reveal the surface of a material at the atomic level and can also provide information about atomic composition. The STM has been used to study biological samples, to analyze industrial materials (such as superconductors, materials that conduct electric current with no resistance at temperatures near zero), and to test miniaturized electronic circuits.