A break junction is a type of electrical contact used in the study of electronic and atomic-scale phenomena. It consists of two metal electrodes separated by a small gap, typically on the order of nanometers to micrometers. The electrodes are brought into contact and then pulled apart, creating a small gap that can be studied under controlled conditions.
Break junctions are used to study a variety of phenomena, including electron transport through single molecules, atomic-scale switching, and the mechanical properties of nanoscale materials. They are particularly useful in the study of molecular electronics, where the electronic properties of individual molecules can be probed by measuring the current flowing through the break junction.
One common method of creating a break junction is to use a piezoelectric crystal to gradually pull the two electrodes apart. As the electrodes are pulled apart, the resistance of the gap between them increases until it reaches a point where the current can no longer flow. This point is known as the “break point”, and can be used to measure the mechanical properties of the material being studied.
Break junctions are also used in scanning tunneling microscopy and atomic force microscopy, where the gap between the electrodes can be used to probe the surface of a sample at atomic resolution.
Overall, break junctions are a valuable tool for studying the properties of materials and electronic devices at the atomic scale, and have applications in fields ranging from materials science to nanotechnology. learn more about Learning Management System.