Fifty years of Hubbard and Anderson lattice models: from magnetism to unconventional superconductivity - A brief overview

Spałek, J.

doi:10.1080/14786435.2014.969352

Cited by 11 publications

(8 citation statements)

References 91 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1). One of the canonical models for the description within the paradigm of strong correlations is the t-J model, 16,[24][25][26][27] in which HTS appears in the range 0 < δ 0.4 in a natural manner already within the renormalized mean field theory RMFT 28,29 , also with the so-called statistical consistency constraints included explicitly (SGA method 30,31 ). The RMFT approach in the SGA version can be related directly to the slave-boson method [32][33][34] (for review see Refs.…”

Section: Introductionmentioning

confidence: 99%

Universal properties of high-temperature superconductors from real-space pairing:t−J−Umodel and its quantitative comparison with experiment

2017

Self Cite

View full text Add to dashboard Cite

Selected universal experimental properties of high temperature superconducting (HTS) cuprates have been singled out in the last decade. One of the pivotal challenges in this field is the designation of a consistent interpretation framework within which we can describe quantitatively the universal features of those systems. Here we analyze in a detailed manner the principal experimental data and compare them quantitatively with the approach based on a single band of strongly correlated electrons supplemented with strong antiferromagnetic (super)exchange interaction (the so-called t-J-U model). The model rationale is provided by estimating its macroscopic parameters on the basis of the 3-band approach for the Cu-O plane. We use our original full Gutzwiller-wave-function solution by going beyond the renormalized mean field theory (RMFT) in a systematic manner. Our approach reproduces very well the observed hole doping (δ) dependence of the kinetic-energy gain in the superconducting phase, one of the principal non-Bardeen-Cooper-Schrieffer features of the cuprates. The calculated Fermi velocity in the nodal direction is practically δ-independent and its universal value agrees very well with that determined experimentally. Also, a weak doping dependence of the Fermi wave-vector leads to an almost constant value of the effective mass in a pure superconducting phase which is both observed in the experiment and reproduced within our approach. An assessment of the currently used models is carried out and the results of the canonical RMFT as a zeroth-order solution are provided for comparison to illustrate the necessity of introduced higher order contributions.

show abstract

Section: Introductionmentioning

confidence: 99%

Universal properties of high-temperature superconductors from real-space pairing:t−J−Umodel and its quantitative comparison with experiment

2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…The t-J Hamiltonian is derived in the strongly correlated regime of the Hubbard model (t U) where an exchange integral J = 4t 2 /U emerges [11,12,16]. Its explicit form for a two-dimensional lattice is given by…”

Section: Model and Methodsmentioning

confidence: 99%

“…Despite its seemingly simple structure, the Hubbard model and its extensions and derivations have been very successful in studying strongly correlated systems [7][8][9][10]. In the strong electron-electron repulsion regime, it is possible to derive an effective model from the Hubbard model in which the doubleoccupancy is discarded according to its extreme energy cost: the so called t-J model [11][12][13][14][15][16]. The Hubbard and the t-J models have been used to theoretically understand and describe so many interesting phenomena such as Mott-Hubbard metal-insulator transition [17], non-Fermi-liquid normal phases and high-temperature superconductivity [18][19][20][21][22][23][24][25][26][27], etc.…”

Section: Introductionmentioning

confidence: 99%

Local properties of the t-J model in a two-pole approximation within COM

Eskandari-asl,

Avella

2021

Preprint

View full text Add to dashboard Cite

In this work, we study the t-J model using a two-pole approximation within the composite operator method. We choose a basis of two composite operators -the constrained electrons and their spin-fluctuation dressing -and approximate their currents in order to compute the corresponding Green's functions. We exploit the algebraic constraints obeyed by the basis operators to close a set of self-consistent equations that is numerically solved. This allows to determine the physical parameters of the system such as the spin-spin correlation function and the kinetic energy. Our results are compared to those of an exact numerical method on a finite system to asses their reliability. Indeed, a very good agreement is achieved through a far less numerically demanding and a more versatile procedure. We show that by increasing the hole doping, anti-ferromagnetic correlations are replaced by ferromagnetic ones. The behavior on changing temperature and exchange integral is also studied and reported.

show abstract

“…The competition between superconductivity and other instabilities of the electron spectrum is a well-known phenomenon, which is interesting from both the theoretical and utilitarian viewpoints [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Such a struggle for the Fermi surface caused by Coulomb forces [43][44][45][46][47][48].…”

Section: Introductionmentioning

confidence: 99%

Quasiparticle conductance-voltage characteristics for break junctions involvingd-wave superconductors: charge-density-wave effects

Ekino¹,

Gabovich²,

Li³

et al. 2017

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

Quasiparticle tunnel conductance-voltage characteristics (CVCs), [Formula: see text], were calculated for break junctions (BJs) made up of layered d-wave superconductors partially gapped by charge-density waves (CDWs). The current is assumed to flow in the ab-plane of electrodes. The influence of CDWs is analyzed by comparing the resulting CVCs with CVCs calculated for BJs made up of pure d-wave superconductors with relevant parameters. The main CDW-effects were found to be the appearance of new CVC peculiarities and the loss of CVC symmetry with respect to the V-sign. Tunnel directionality was shown to be one of the key factors in the formation of [Formula: see text] dependences. In particular, the orientation of electrodes with respect to the current channel becomes very important. As a result, [Formula: see text] can acquire a large variety of forms similar to those for tunnel junctions between superconductors with s-wave, d-wave, and mixed symmetry of their order parameters. The diversity of peculiarities is especially striking at finite temperatures. In the case of BJs made up of pure d-wave superconductors, the resulting CVC can include a two-peak gap-driven structure. The results were compared with the experimental BJ data for a number of high-T oxides. It was shown that the large variety of the observed current-voltage characteristics can be interpreted in the framework of our approach. Thus, quasiparticle tunnel currents in the ab-plane can be used as an additional mean to detect CDWs competing with superconductivity in cuprates or other layered superconductors.

show abstract

Fifty years of Hubbard and Anderson lattice models: from magnetism to unconventional superconductivity - A brief overview

Cited by 11 publications

References 91 publications

Universal properties of high-temperature superconductors from real-space pairing:t−J−Umodel and its quantitative comparison with experiment

Universal properties of high-temperature superconductors from real-space pairing:t−J−Umodel and its quantitative comparison with experiment

Local properties of the t-J model in a two-pole approximation within COM

Quasiparticle conductance-voltage characteristics for break junctions involvingd-wave superconductors: charge-density-wave effects

Contact Info

Product

Resources

About