Theory of Unconventional Superconductivity in Strongly Correlated Systems: Real Space Pairing and Statistically Consistent Mean-Field Theory - in Perspective

• Authors: J. Spałek
• Languages of publication: EN

Abstracts

EN

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.

Keywords

EN

71.27.+a; 74.70.Tx; 74.20.-z

Discipline

• 74.20.-z: Theories and models of superconducting state
• 71.27.+a: Strongly correlated electron systems; heavy fermions
• 74.70.Tx: Heavy-fermion superconductors(for heavy-fermion systems in magnetically ordered materials, see 75.30.Mb; see also 71.27.+a Strongly correlated electron systems, heavy fermions)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2012
• Volume: 121
• Issue: 4
• Pages: 764-784

Dates

published

2012-04

Contributors

author

J. Spałek

• Marian Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków, Poland
• Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Reymonta 19, 30-059 Kraków, Poland

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Identifiers

DOI

10.12693/APhysPolA.121.764