Related papers: Exact Solution of a Electron System Combining Two …
An integrable spin-ladder model with nearest-neighbor exchanges and biquadratic interactions is proposed. With the Bethe ansatz solutions of the model hamiltonian, it is found that there are three possible phases in the ground state, i.e.,…
We consider the two-band Hubbard model, where electrons from different bands interact through an on-site one- and two-particle hybridization. The proposed Hamiltonian makes it possible to construct an effective theory and answer the…
The generalized t-J model conserving the number of double occupancies is constructed from the Hubbard model at and in the vicinity of half-filling at strong coupling. The construction is realized by a self-similar continuous unitary…
A novel effective Hamiltonian in the subspace of singly occupied states is obtained by applying the Gutzwiller projection approach to a generalized Hubbard model with the interactions between two nearest- neighbor sites. This model provides…
Strongly interacting fermions represent the key constituent of several intriguing phases of matter. However, due to the inherent complexity of these systems, important regimes are still inaccessible. Here, we derive a realistic and flexible…
The Hofstadter model describes non-interacting fermions on a lattice in the presence of an external magnetic field. Motivated by the plethora of solid-state phases emerging from electron interactions, we consider an interacting version of…
One-electron self-energy in the $t$-$J$ model was computed using a recently developed large-$N$ method based on the path integral representation for Hubbard operators. One of the main features of the self-energy is its strong asymmetry with…
A coherent state representation for the electrons of ordered antiferromagnets is used to derive effective Hamiltonians for the dynamics of holes in such systems. By an appropriate choice of these states, the constraint of forbidden double…
We numerically investigate the ground state of the extended $t$-$J$ Hamiltonian with periodic local modulations in one dimension by using the density-matrix renormalization group method. Examining charge and spin excitation gaps, as well as…
A new lattice model is presented for correlated electrons on the unrestricted $4^L$-dimensional electronic Hilbert space $\otimes_{n=1}^L{\bf C}^4$ (where $L$ is the lattice length). It is a supersymmetric generalization of the Hubbard…
The properties of a dilute electron gas, coupled to the lattice degrees of freedom, are studied and compared with the properties of an electron gas at half-filling, where spinless fermions with two orbitals per lattice site are considered.…
A recently proposed strongly correlated electron system associated with the Temperley-Lieb algebra is solved by means of the coordinate Bethe ansatz for periodic and closed boundary conditions.
We have investigated the formation of bound state of two electrons in different kind of lattices using a t-J-U model.
Different scenarios of the implementation of the two-band model in strongly correlated electrons systems, including frustrated magnets, high-temperature superconductors, and Kondo lattices, are considered. The interaction of current…
We propose a simple idea to construct 1D integrable models with impurities. We illustrate the strategy for a supersymmetric $t-J$ Hamiltonian in considerable detail. The impurity comprises the local deformation of the hopping and exchange…
The free energy of the supersymmetric $t-J$ model is expressed in terms of finite temperature excitations above thermodynamic equilibrium. This reveals that the free energy has the form of noninteracting fermions with temperature dependant…
The generalization of the Yang-Baxter equations (YBE) in the presence of Z_2 grading along both chain and time directions is presented and an integrable model of t-J type with staggered disposition along a chain of shifts of the spectral…
An exactly solvable strongly correlated electron model with two independent parameters is constructed in the frame of the quantum inverse scattering method, which can be seen as a generalization of the Bariev model. Through the Bethe ansatz…
Interaction of a two-level atom with a single mode of electromagnetic field including Kerr nonlinearity for the field and intensity-dependent atom-field coupling is discussed. The Hamiltonian for the atom-field system is written in terms of…
To explore the nature of the metallic state near the transition to a Mott insulator we investigate the t-J model with random exchange interaction in d=infinity dimensions. A numerically exact solution is obtained by an extension of the…