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arXiv · 1202.2833

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

Józef Spałek
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Abstract

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 $\sim tx$, 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.

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Józef Spałek. 2012-02-13. Theory of Unconventional Superconductivity in Strongly Correlated Systems: Real Space Pairing and Statistically Consistent Mean-Field Theory - in Perspective. https://doi.org/10.12693/aphyspola.121.764

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