相关论文: Revisit Phase Separation of the Two-Dimensional $t…
The boundary of phase separation of the two-dimensional t-J model is investigated by the power-Lanczos method and Maxwell construction. The method is similar to a variational approach and it determines the lower bound of the phase…
We investigate the phase diagram of the two-dimensional t-J model using a recently developed Green's Function Monte Carlo method for lattice fermions. We use the technique to calculate exact ground-state energies of the model on large…
We develop a general numerical method to study the zero temperature properties of strongly correlated electron models on large lattices. The technique, which resembles Green's Function Monte Carlo, projects the ground state component from a…
A simple variation of the Lanczos method is discussed. The new technique is based on a systematic reduction of the size of the Hilbert space of the model under consideration. As an example, the two dimensional ${\rm t-J_z}$ model of…
The two-dimensional $t$-$J$ model in the ground state is investigated by the power Lanczos method. The pairing-pairing correlation function for $d_{x^2-y^2}$-wave symmetry is enhanced in the realistic parameter regime for high-$T_c$…
We have studied the t-J model using the Green Function Monte Carlo technique. We have obtained accurate energies well converged in the thermodynamic limit, by performing simulations up to 242 lattice sites. By studying the energy as a…
The initial trial wave function used in a simple ground-state projection method, the power method, is systematically improved by using Lanczos algorithm. Much faster convergence to the ground state achieved by using these wave functions…
The phase diagram of the two-dimensional t-J model is determined accurately at low electron density by a combination of analytic and numerical techniques. The ground state exhibits three phases in the limit of zero electron density: an…
From calculations of the high temperature series for the free energy of the two-dimensional t-J model we construct series for ratios of the free energy per hole. The ratios can be extrapolated very accurately to low temperatures and used to…
We reported that the pair-pair correlation function of the two-dimensional t-J model does not have long-range d-wave superconducting correlations in the interesting parameter range of $J/t \leq 0.5$. The power-Lanczos method is used under…
Two-dimensional t-J model is studied by a variational Monte Carlo method, using Gutzwiller-Jastrow-type wave functions. Various kinds of superconducting pairing symmetries are compared in order to determine the phase diagram of the ground…
The pair-pair correlation function of the two-dimensional t-J model is studied by using the power-Lanczos method and an assumption of monotonic behavior. In comparison with the results of the ideal Fermi gas, we conclude that the 2D t-J…
The phase separation boundary of isotropic t-J ladders is analyzed using density matrix renormalization group techniques. The complete boundary to phase separation as a function of J/t and doping is determined for a chain and for ladders…
We discuss the occurrence and the stability of charge density plateaux in ladder-like $t-J$ systems (at zero magnetization M=0) for the cases of 2- and 3-leg ladders. Starting from isolated rungs at zero leg coupling, we study the behaviour…
We make a critical analysis of numerical results for and against phase separation and stripe formation in the t-J model. We argue that the frustrated phase separation mechanism for stripe formation requires phase separation at too high a…
We investigate the phase diagram of the two dimensional {\it t}-{\it J} model using a recently developed technique that allows to solve the mean-field model hamiltonian with a variational calculation. The accuracy of our estimate is…
The spin and density correlation functions of the two-dimensional Hubbard model at low electronic density $<n>$ are calculated in the ground state by using the power method, and at finite temperatures by using the quantum Monte Carlo…
We study the ground state of the one-dimensional "$t$-$J_s$-$J_{\tau}$ model," which is a variant of the $t$-$J$ model with additional channel degree of freedom. The model is not only a generalization of the $t$-$J$ model but also an…
Series expansions at T=0 are used to study properties of the half-filled $t-J$ ladder doped with one or two holes, and at quarter filling. Dispersion curves are obtained for one-hole symmetric and antisymmetric (bonding and antibonding)…
Fixed-node Green's function Monte Carlo calculations have been performed for very large 16x6 2D Hubbard lattices, large interaction strengths U=10,20, and 40, and many (15-20) densities between empty and half filling. The nodes were fixed…