Related papers: Absence of the d-Density Wave State in 2D Hubbard …
Proposals for superconductivity emerging from correlated electrons in the doped Hubbard model on the honeycomb lattice range from chiral $d+id$ singlet to $p+ip$ triplet pairing, depending on the considered range of doping and interaction…
Even at weak to intermediate coupling, the Hubbard model poses a formidable challenge. In two dimensions in particular, standard methods such as the Random Phase Approximation are no longer valid since they predict a finite temperature…
We investigate electronic properties of the doped two-leg Hubbard ladder with both the onsite and the nearest-neighbor Coulomb repulsions, by using the the weak-coupling renormalization-group method. It is shown that, for strong…
We study the electronic instabilities in a 2D Hubbard model where one of the dimensions has a finite width, so that it can be considered as a large array of coupled chains. The finite transverse size of the system gives rise to a discrete…
Recent scanning tunneling microscopy (STM) experiments of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ have shown evidence of real-space organization of electronic states at low energies in the pseudogap state. We argue based on symmetry…
A momentum space, mean field d-density wave (DDW) Hamiltonian is investigated self-consistently. The pseudo-gapped(PG)state of YBCO is assumed to correspond to the pure DDW state. A relation between thermodynamic potential of the system and…
A model study for the coexistence of the spin density wave and superconductivity is presented. With reference to the recent angle resolved photo emmission experimental data in high T_c cuprates, presence of the nested pieces of bands is…
We start with the chiral density wave(CDW)mean field Hamiltonian in the momentum space for the pseudo-gapped state of YBCO in the absence of magnetic field, including the momentum conserving inter-layer tunneling matrix elements in the…
Densities and transition densities are computed in an equilateral triangular alpha-cluster model for $^{12}$C, in which each $\alpha$ particle is taken as a gaussian density distribution. The ground-state, the symmetric vibration (Hoyle…
New quantum phenomena are continuously being discovered in 2D systems. In particular, the charge density wave (CDW) has the aspect of a quantum crystal with a macroscopic wave function (order parameter), so unlike quantum liquids…
We use an unbiased, continuous-time quantum Monte Carlo method to address the possibility of a zero-temperature phase without charge-density-wave (CDW) order in the Holstein and, by extension, the Holstein-Hubbard model on the half-filled…
The dynamical cluster approximation (DCA) is a quantum cluster extension to the single-site dynamical mean-field theory that incorporates spatially nonlocal dynamic correlations systematically and nonperturbatively. The DCA$^+$ algorithm…
The recently demonstrated x-ray scattering approach using a free electron laser with a high field pulsed magnet has opened new opportunities to explore the charge density wave (CDW) order in cuprate high temperature superconductors. Using…
Charge density wave (CDW) correlations have recently been shown to universally exist in cuprate superconductors. However, their nature at high fields inferred from nuclear magnetic resonance is distinct from that measured by x-ray…
The two-dimensional repulsive Hubbard model has been investigated by a variety of methods, from small to large U. Superconductivity with d-wave symmetry is consistently found close to half filling. After a brief review of the various…
We investigate the bilayer model with two layers of imbalanced densities coupled by the interlayer hybridization. Using the large-scale dynamical cluster quantum Monte Carlo simulation, we discovered that increased hybridization induces a…
At temperatures above the superconducting transition temperature the pairfield susceptibility provides information on the nature of the pairfield fluctuations. Here we study the d-wave pairfield susceptibility of a 2D Hubbard model for…
The low-temperature thermal conductivity \kappa_0/T of d-wave superconductors is generally thought to attain a "universal" value independent of disorder at sufficiently low temperatures, providing an important measure of the magnitude of…
When superconducting (SC) and charge-density wave (CDW) orders compete, novel low temperature behaviors can result. From an analysis of the Landau-Ginzberg-Wilson theory of competing orders, we demonstrate the generic occurrence of a…
The transition between a metallic and a pseudogap phase in high-$T_c$ cuprate superconductors is the subject of experimental investigations but has not been settled theoretically, even within the context of the Hubbard model. We apply the…