Related papers: Impurities and Defects in Mott Systems
Theoretical studies of disordered $d$-wave superconductors have focused, with a few exceptions, on optimally doped models with strong scatterers. Addressing recent controversies about the nature of the overdoped cuprates, however, requires…
Inelastic light scattering is an intensively used tool in the study of electronic properties of solids. Triggered by the discovery of high temperature superconductivity in the cuprates and by new developments in instrumentation, light…
The specific heat jump at a normal-superconducting phase transition in an anisotropic superconductor with nonmagnetic impurities is calculated within a weak-coupling mean field approximation. It is shown that its dependence on the impurity…
Applying a variational Monte Carlo method to a two-dimensional t-J model, we study the nonmonotonic d_{x^2-y^2}-wave superconductivity, observed by Raman scattering and ARPES experiments in the electron-doped cuprates. As a gap function in…
The Bechgaard salts and the high T$_c$ cuprates are described by two and three band models, respectively, with the lowest band (nearly) half filled. In organics the interactions are small, while in cuprates the repulsion $U_d$ on the Cu…
Neutron scattering experiments continue to improve our knowledge of spin fluctuations in layered cuprates, excitations that are symptomatic of the electronic correlations underlying high-temperature superconductivity. Time-of-flight…
We consider the effect of non-magnetic impurities in a $d_{x^2 - y^2}$ superconductor with $\ef$ close to a van Hove singularity. It is shown that the non-trivial density of states (DOS) allows for resonant scattering already at…
We argue that aspects of the anomalous, low temperature, spin and charge dynamics of the high temperature superconductors can be understood by studying the corresponding physics of undoped Mott insulators. Such insulators display a quantum…
The electronic structure of cuprate superconductors is studied within the kinetic energy driven superconducting mechanism in the presence of the out-of-plane impurities. With increasing the impurity concentration, although both…
In the cuprate superconductors, superconductivity often co-exists with other types of order, including charge density wave and nematic orders. Over the past decade, resonant x-ray scattering has emerged as a key tool to investigate these…
Besides superconductivity, copper-oxide high temperature superconductors are susceptible to other types of ordering. We use scanning tunneling microscopy and resonant elastic x-ray scattering measurements to establish the formation of…
We deal with a model for high-temperature superconductivity which maintains that in cuprates electrons running in the copper oxide layers, found in lattice of these materials, form spin-singlet bonds with electrons running in the…
We investigate the nematic and loop-current type orders that may arise as vestigial precursor phases in a model with an underlying pair-density wave (PDW) instability. We discuss how such a vestigial phase gives rise to a highly anisotropic…
We present a self-consistent theory of current-voltage characteristics of d-wave/d-wave contacts at arbitrary transparency. In particular, we address the open problem of the observation of subharmonic gap structure (SGS) in cuprate…
We study electron transport through a domain wall in a ferromagnetic nanowire subject to spin-dependent scattering. A scattering matrix formalism is developed to address both coherent and incoherent transport properties. The coherent case…
In our short review, we consider the transport properties of strongly correlated Fermi systems like heavy fermion metals and high-$T_c$ superconductors. Their transport properties are defined by strong inter-particle interaction forming…
We analyze pseudogap phenomena widely observed in the underdoped cuprates. We assume the existence of a strong d-wave pairing force competing with antiferromagnetic(AFM) fluctuations and the formation of flat and damped dispersion around…
In this thesis, we theoretically examine the pairing mechanisms and the identification of the pairing symmetry of unconventional superconductors whose normal states are correlated, multiband, or topological. In the first part, we…
Based on recently proposed anti-ferromagnetic spin fluctuation exchange models for $d_{x^2-y^2}$-superconductors, we show that coupling to harmonic phonons {\it{cannot}} account for the observed isotope effect in the cuprate high-$T_c$…
Substitutional impurities in the CuO2 planes of the cuprates allow us to probe the electronic properties of the host material. The pseudo-gap in the underdoped regime is unmodified far from the impurities even though Tc is greatly reduced.…