Related papers: Bosons, gauge fields, and high-Tc cuprates
We study the effect of a strongly fluctuating gauge field on a degenerate Bose liquid, relevant to the charge degrees of freedom in doped Mott insulators. We find that the superfluidity is destroyed. The resulting metallic phase is studied…
We study a two-dimensional system of bosons interacting with a fluctuating U(1) gauge field with overdamped dynamics. We find two instabilities of the condensed phase at T=0: one to phase separation and another to a homogeneous…
A consistent microscopic theory of pseudogap phenomena and novel Bose-liquid superconductivity (superfluidity) is presented, based on the fact that in high-$T_c$ cuprates and related systems the energy $\varepsilon_A$ of the effective…
I consider models with an impurity spin coupled to a fluctuating gaussian field with or without additional Kondo coupling of the conventional sort. In the case of isotropic fluctuations, the renormalisation group flows for these models have…
We investigate an ultracold and dilute Bose gas by taking into account a finite-range two-body interaction. The coupling constants of the resulting Lagrangian density are related to measurable scattering parameters by following the…
The origin of electron-boson interactions is central to understanding high-$T_c$ superconductivity in cuprates. While phonons and magnetic fluctuations are widely considered as candidates for mediating electron pairing, the role of charge…
We study 2+1 dimensional massless Dirac fermions and bosons coupled to a U(1) gauge field as a model for underdoped cuprates. We find that the uniform susceptibility and the specific heat coefficient are logarithmically enhanced (compared…
Recent observation of diminishing superfluid phase stiffness upon increasing carrier density in cuprate high-temperature superconductors is unexpected from the quantum density-phase conjugation of superfluidity. Here, through analytic…
We present a self-consistent approach to deal with the pairing-fluctuation effects in quasi-two-dimensional superconducting systems. Besides the Cooper pairs in the Bose-Einstein condensate, there are pairs occupying the excited states,…
General field theory of a fluctuating d-wave superconductor is constructed and proposed as an effective description of superconducting cuprates at low energies. The theory is used to resolve a puzzle posed by recent experiments on…
The Gaussian fluctuations in slave-boson mean-field theory of $t-J$ model is analyzed in this paper in the low-doping regime where the superconducting to normal (pseudo-gap phase) transition is driven by vanishing of bose-condensation…
Combining (1) the universal correlations between $T_{c}$ and $n_{s}/m^{*}$ (superconducting carrier density / effective mass) and (2) the pseudo-gap behavior in the underdoped region, we obtain a picture to describe superconductivity in…
The c-field simulation technique is used to study a trapped quasi-two dimensional Bose gas. We calculate the central curvature of the system density and fluctuations of the condensate mode in the degenerate regime. These results provide new…
In this paper, we present our studies of the phase diagram of the cuprate superconductors performed in recent years. We describe how a few field-theoretical concepts can be used to account for the puzzling properties of these compounds.…
Normal state orbital diamagnetism of charged bosons quantitatively accounts for recent high-resolution magnetometery results near and above the resistive critical temperature Tc of superconducting cuprates. Our parameter-free descriptions…
One of the pivotal questions in the physics of high-temperature superconductors is whether the low-energy dynamics of the charge carriers is mediated by bosons with a characteristic timescale. This issue has remained elusive since…
The optical response of a system of two-dimensional Bose condensate droplets with an internal charge structure interacting with impurities is considered within the mode-coupling theory. It is found, that the glass transition in the system…
One of the first finding concerning the superconducting (SC) density $n_{\rm sc}$ in cuprates was their small magnitudes that revealed the importance of phase fluctuations. More recently, measurements in a variety of overdoped cuprates…
We first consider an exactly solvable classical field model to understand the coherence properties and the density fluctuations of a one-dimensional (1D) weakly interacting degenerate Bose gas with repulsive interactions at temperatures…
We present a 2+1-dimensional lattice model for the copper oxide superconductors and their parent compounds, in which both the charge and spin degrees of freedom are treated dynamically. The spin-charge coupling parameter is associated to…