The Bardeen tool, named after its inventor John Bardeen, is a device used in experimental physics to measure the electrical conductivity of materials at low temperatures. The tool is essentially a probe made of a thin wire which is connected to a voltage source and is used to measure the resistance of the material being studied. The Bardeen tool has been instrumental in the discovery and study of superconductivity, a phenomenon where certain materials lose all resistance to electrical current at very low temperatures. It has also been used to investigate the behavior of semiconductors and other materials with unique electrical properties. The tool has been widely used in the field of condensed matter physics and has helped to advance our understanding of the behavior of matter at the atomic level.
