Related papers: Finitely Correlated Generalized Spin Ladders
We introduce a new two-dimensional model with diagonal four spin exchange and an exactly knownground-state. Using variational ansaetze and exact diagonalisation we calculate upper and lower bounds for the critical coupling of the model.…
Employing mainly numerical methods, we explore the ground-state phase diagram of an anisotropic $S=1/2$ ladder, in which leg interactions are uniform and isotropic, while rung interactions are alternating and have a common Ising-type…
Motivated by the co-existing charge and spin order found in strongly correlated ladder systems, we study an effective pseudospin model on a coupled two-leg ladder. A bosonisation analysis yields a rich phase diagram showing Wigner/Peierls…
The spin-1/2 Ising-Heisenberg two-leg ladder accounting for alternating Ising and Heisenberg inter-leg couplings in addition to the Ising intra-leg coupling is rigorously mapped onto to a mixed spin-(3/2,1/2) Ising-Heisenberg diamond chain…
The mixed spin-(1,1/2) Ising-Heisenberg double sawtooth ladder containing mixture of both spin-1 and spin-1/2 nodal atoms, and the spin-1/2 interstitial dimers is approximately solved by the transfer-matrix method. Here, we study in detail…
The paper discusses the transformation of decorated Ising models into an effective \textit{undecorated} spin models, using the most general Hamiltonian for interacting Ising models including a long range and high order interactions. The…
We introduce a class of exactly solvable SO(n) symmetric Hamiltonians with matrix product ground states. For an odd $n\geq 3$ case, the ground state is a translational invariant Haldane gap spin liquid state; while for an even $n\geq 4$…
We study frustrated quantum spin systems consisting of dimers of spin-1/2 spins. We derive several models that have the exact ground state of the form of the direct product of dimer states. The ground states realized include the product…
A large number of symmetry-protected topological (SPT) phases have been hypothesized for strongly interacting spin-1/2 systems in one dimension. Realizing these SPT phases, however, often demands fine-tunings hard to reach experimentally.…
Characterizing and accessing quantum phases of itinerant bosons or fermions in two dimensions (2D) that exhibit singular structure along surfaces in momentum space but have no quasi-particle description remains as a central challenge in the…
We theoretically study the ground-state phase diagram of strongly interacting bosons on a generalized zig-zag ladder model, the rail-road trestle (RRT) model. By means of analytical arguments in the limits of decoupled chains and the case…
We investigate the phase diagram of a quarter filled Hubbard ladder with nearest-neighbor Coulomb repulsion using bosonization and renormalization group approach. Focusing on the strong-repulsion regime, we discuss the effect of an…
We present a two-parameter family of exactly solvable quantum many-body systems in one spatial dimension containing the Lieb-Liniger model of interacting bosons as a particular case. The principal building block of this construction is the…
We use exact diagonalization and the modified Lanczos method to study the finite energy and finite momentum spectral weight of the longitudinal and transverse spin excitations of the anisotropic zig-zag ladder. We find that the spin…
The ground-state phase diagram of Heisenberg spin-1/2 system on a two-leg ladder with rung alternation is studied by combining analytical approaches with numerical simulations. For the case of ferromagnetic leg exchanges a unique…
We investigate the influence of biquadratic exchange interactions on the low-lying excitations of a S=1/2-ladder using perturbation theory, numerical diagonalization of finite systems and exact results for ladders with matrix product ground…
We report density-matrix renormalization group calculations of spin gaps in the quarter-filled correlated two-leg rectangular ladder with bond-dimerization along the legs of the ladder. In the small rung-coupling region, dimerization along…
Using Density-Matrix Renormalization Group, we investigate the general phase diagram of the frustrated two-leg ladder with Heisenberg interactions along legs, rungs and diagonals. We confirm that all antiferromagnetic gapped states belong…
Motivated by the work of Kitaev, we construct an exactly soluble spin-$\frac{1}2$ model on honeycomb lattice whose ground states are identical to $\Delta_{1x}p_x+\Delta_{1y}p_y+i(\Delta_{2x}p_x+\Delta_{2y}p_y)$-wave paired fermions on…
We study the excitation spectrum of the two-chain S=1/2 Heisenberg spin ladder with additional inter-chain second-neighbor frustrating interactions. The one and two-particle excitations are analyzed by using a mapping of the model onto a…