The exploratory research of a Novel gyroscope based on superfluid Josephson effect

Abstract

A new concept gyroscope based on superfluid Josephson effect was described and analyzed to improve the performance greatly. It is a new Sagnac effect that an interferometer “loop”, formed by placing double weak links in a toroid filled with superfluid He4, can detect the interference of superfluid matter waves generated by the AC Josephson oscillation in weak links. In this paper, the potential advantages of superfluid gyroscope were estimated. The most important advantage is the very high sensitivity which could be increased theoretically by a factor of 1010 than the sensitivity of traditional Ring Laser Gyroscope. But such a superfluid gyroscope still faces some difficulties when it is used as an angular velocity measuring device for navigation, the most important one is the conflict between the high sensitivity and wide measurement range. Then, two methods were discussed to solve that conflict which is a key problem in current superfluid gyroscope research. The first method is “flux-locking”, which is a technique used in superconducting dc-SQUIDs. The principle of the method and analysis of performance were presented. It can increase measurement range to 500 times of original one. In another hand, such a superfluid gyroscope should work in a situation with limited angular acceleration. Author presented another method, called “history tracing”, and its work principle. The performance of the second method also be studied, and results showed that “history tracing” overcomes the problem of measurement range totally. Comparisons showed that “history tracing” is a better choice to develop high performance superfluid gyroscope.