Abstract
This thesis reports the discovery of Josephson effect, and describes the content of Josephson effect, especially introduces the deduction of the Josephson formula. We discusses the specific circumstances of DC Josephson effect and AC Josephson effect .The former applied zero voltage. Superconducting electron pairs can tunnel through the insulating layer and form superconducting current without the phenomenon of potential difference; The latter is when the superconductor junctions under the action of the DC voltage, it will come of the characteristics of alternating current and radiating electromagnetic. Then, we discusses their own principles and characteristics by the formula and the parameters, focuses on the analysis of the superconducting quantum interferometer and finally describes the application of the Josephson effect. With so many advantages such as the less inherent noise, sensitivity and high switching speed, etc., Josephson instruments have made many important advances possible in practice, and have great potential. With the further development of superconducting technology, the application of Josephson effect will be more extensive.
Keywords: DC Josephson effect; AC Josephson effect; Superconducting quantum interference; Superconductivity
