Related papers: Non-Fermi liquid and pairing in electron-doped cup…
We apply the spin-fermion model to study the normal state and pairing instability in electron-doped cuprates near the antiferromagnetic QCP. Peculiar frequency dependencies of the normal state properties are shown to emerge from the…
We consider normal state properties, the pairing instability temperature, and the structure of the pairing gap in electron-doped cuprates. We assume that the pairing is mediated by collective spin excitations, with antiferromagnetism…
We argue that the experimentally observed nonmonotonic gap in electron-doped cuprates at optimal doping is the lowest quasiparticle excitation energy in the coexisting antiferromagnetic (AF) and superconducting (SC) state. The idea is…
Based on an unconventional Fermi liquid model, we present several results on the optimally doped and overdoped cuprate superconductors. For the normal state, we provide an analytic demonstration, backed by self-consistent Baym-Kadanoff (BK)…
Cuprate high-T_c superconductors on the Mott-insulating side of "optimal doping" (with respect to the highest T_c's) exhibit enigmatic behavior in the non-superconducting state. Near optimal doping the transport and spectroscopic properties…
Spectral functions are evaluated numerically within the t-t'-J model as relevant for electron-doped cuprates. The Fermi surface develops from a pocket-like into a large one with doping. The corresponding pseudogap in the nodal direction is…
Based on a Fermi liquid model, we present several results on the normal state of the optimally doped and overdoped cuprate superconductors. Our main result is an analytic demonstration, backed by self-consistent numerical calculations, of…
We revisit the problem of spin-mediated superconducting pairing at the antiferromagnetic quantum-critical point with the ordering momentum ({\pi},{\pi}) = 2k_F. The problem has been previously considered by one of the authors. However, it…
In this paper we continue our analysis of the interplay between the pairing and the non-Fermi liquid behavior in a metal for a set of quantum-critical (QC) systems with an effective dynamical electron-electron interaction $V(\Omega_m)…
A scenario is presented, in which the presence of a quantum critical point due to formation of incommensurate charge density waves accounts for the basic features of the high temperature superconducting cuprates, both in the normal and in…
Cooper's formalism for fermionic pairing has been revisited considering upto 3rd neighbour hopping terms, firstly with a Fermi liquid like background on a square lattice keeping in mind the overdopped cuprates. Then the whole scheme is…
We address the issue whether the data on optical conductivity and Raman scattering in electron-doped cuprates below $T_c$ support the idea that the $d-$wave gap in these materials is non-monotonic along the Fermi surface. We calculate the…
We study the electronic instabilities of newly predicted Ni-based high-$T_c$ superconducting material La$_2$Ni$_2$Se$_2$O$_3$ based on the random phase approximation. Our calculations on the susceptibility indicate that the collinear…
We propose a possible scenario for the new metallic conductivity of underdoped and optimally doped cuprates. Charge carriers are assumed to be large polarons which form a Fermi-liquid and Cooper-like pairs below a crossover tempurature…
In this paper a mean-field theory for the spin-liquid paramagnetic non-superconducting phase of the p- and n-type High-$T_c$ cuprates is developed. This theory applied to the effective $t-t'-t''-J^*$ model with the {\it ab initio}…
We report an angular quantum oscillation study of Tl_2Ba_2CuO_{6+delta} for two different doping levels (Tc = 10K and 26 K) and determine the Fermi surface size and topology in considerable detail. Our results show that Fermi liquid…
We analyze a class of quantum-critical models, in which momentum integration and the selection of a particular pairing symmetry can be done explicitly, and the competition between non-Fermi liquid and pairing can be analyzed within an…
Doping and strain dependences of the electronic structure of the CuO6-octahedra layer within LDA+GTB method in the frameworks of six-band p-d model are calculated. Band structure and Fermi surface of the quasiparticle excitations in the…
The density-of-states at the Fermi energy, $N(E_F)$, is low in doped superconducting semiconductors and high-$T_C$ cuprates. This contrasts with the common view that superconductivity requires a large electron-boson coupling $\lambda$ and…
We consider a quantum-critical metal with interaction mediated by fluctuations of a critical order parameter. This interaction gives rise to two competing tendencies -- pairing and non-Fermi liquid behavior. Due to competition, the pairing…