First-order phase transitions in superconducting films: A Euclidean model

الأصل · EN

In the context of the Ginzburg--Landau theory for critical phenomena, we consider the Euclidean λϕ⁴+ηϕ⁶ model bounded by two parallel planes, a distance L separating them. This is supposed to describe a sample of a superconducting material undergoing a first-order phase transition. We are able to determine the dependence of the transition temperature Tc for the system as a function of L. We show that % Tc(L) is a concave function of L, in qualitative accordance with some experimental results. The form of this function is rather different from the corresponding one for a second-order transition.