The Beresinskii-Kosterlitz-Thouless transition and its application to superconductors

by Dr Lara Benfatto (ISC-CNR)

Tuesday 25 Oct 2016, 16:00 → 18:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)

More than 40 years after the seminal work by Berezinskii, Kosterlitz, and Thouless the BKT transition remains one of the most spectacular phenomena in condensed matter systems, as it has been acknowledged by the 2016 Nobel Prize. Even though it was originally formulated within the context of the two-dimensional XY model for classical spins, it represents the paradigm for the superfluid transition in two dimensions. As such, it has been the subject of an intense theoretical and experimental investigation in a variety of systems, ranging from thin films of superconductors to artificial heterostructures and cold atoms. In this talk, I will give an introduction to the basic ingredients of the BKT transition and I will discuss the challenges emerged in the last few years regarding its observation in quasi-two-dimensional superconducting and superfluid systems.