Fluctuation Phenomena in Superconductors

The phase transitions and superconductivity are the two summits of physics which were conquered in the second part of the twentieth century. They are connected by the mountain-range, which is called superconducting fluctuations. My lecture will be devoted to discussion of the latter.

I will start from recalling of some facts of the history of superconductivity and then concentrate on the novel superconductors, where fluctuations play an important role. I will discuss their wave nature close to critical temperature remaining in the framework of Ginzburg-Landau ideas, using only the Heisenberg principle, and handwaving to obtain the necessary evaluations. Then, moving along the line, separating superconducting and normal phase in the phase diagram “temperature-magnetic field”, I will approach the point of quantum phase transition at zero temperature and will show how the waves break in vortices and the Abrikosov’s lattice is formed.

Finally I will show several impressive manifestations of superconducting fluctuations in physical properties of superconductors and will explain how they can be used in order to investigate the modern superconducting systems.