Theory of unconventional superconductivity in strongly correlated systems : real space pairing and statistically consistent mean-field theory : in perspective
Theory of unconventional superconductivity in strongly correlated systems : real space pairing and statistically consistent mean-field theory : in perspective
Theory of unconventional superconductivity in strongly correlated systems : real space pairing and statistically consistent mean-field theory : in perspective
author:
Spałek Józef
journal title:
Acta Physica Polonica. A
title of volume:
Proceedings of the XV-th National School "Hundred Years of Superconductivity", Kazimierz Dolny, October 9-13, 2011 and Proceedings of the 9th National Symposium of Synchrotron Radiation Users, Warsaw, September 26-27, 2011 and Selected papers presented at the Tenth Symposium of Magnetic Measurements, Warsaw, September 17-19, 2011
In this brief overview we discuss the principal features of real space pairing as expressed via corresponding low-energy (t J or periodic Anderson-Kondo) effective Hamiltonian, as well as consider concrete properties of those unconventional superconductors. We also rise the basic question of statistical consistency within the so-called renormalized mean-field theory. In particular, we provide the phase diagrams encompassing the stable magnetic and superconducting states. We interpret real space pairing as correlated motion of fermion pair coupled by short-range exchange interaction of magnitude J comparable to the particle renormalized band energy ≈ tx, where x is the carrier number per site. We also discuss briefly the difference between the real-space and the paramagnon-mediated sources of superconductivity. The paper concentrates both on recent novel results obtained in our research group, as well as puts the theoretical concepts in a conceptual as well as historical perspective. No slave-bosons are required to formulate the present approach.
number of pulisher's sheets:
1,3
affiliation:
Wydział Fizyki, Astronomii i Informatyki Stosowanej : Instytut Fizyki im. Mariana Smoluchowskiego