THE LITTLE-PARKS EFFECT IN AN INHOMOGENEOUS SUPERCONDUCTING RING

An inhomogeneous superconducting ring (hollow cylinder) placed in a ma gnetic field is considered. It is shown that the superconducting trans ition of the section with the lowest critical temperature may be a fir st order phase transition if the magnetic flux contained within the ri ng is not divisible by the flux quantum. In the vicinity of this trans ition, thermal fluctuations carl induce the voltage in the ring with r ather small sizes.