What is the principle behind a Scanning Tunneling Microscope (STM)?
The STM operates on the principle of quantum tunneling. When a conductive tip is brought very close to a conductive sample, a bias voltage applied between the tip and the sample allows electrons to tunnel through the vacuum gap. The resulting tunneling current is highly sensitive to the tip-sample distance, enabling atomic-scale resolution. STMs are used to image surfaces at the atomic level and manipulate individual atoms.
