Related papers: N-leg integer-spin ladders and tubes in commensura…
We analyze the low-energy dynamics of quasi one dimensional, large-$S$ quantum antiferromagnets with easy-axis anisotropy, using a semi-classical non-linear sigma model. The saddle point approximation leads to a sine Gordon equation which…
Topological nodal-line semimetals exhibit double or fourfold degenerate nodal lines, which are protected by symmetries. Here, we investigate the possibility of the existence of triply degenerate nodal lines in metals. We present two types…
We numerically investigate the ground-state phase diagram of the $S=1/2$ ferromagnetic-antiferromagnetic bond-alternating chain, in which the ferromagnetic interactions are stronger than the antiferromagnetic ones, and the anisotropies of…
Spin models that have been proposed to describe dimerized chains, ladders, two dimensional antiferromagnets, and other compounds are here studied when some spins are replaced by spinless vacancies, such as it occurs by $Zn$ doping. A small…
Because the three-leg ladder behaves like a renormalized single Heisenberg chain we argue that a spin-Peierls instability must occur in this system when it is coupled to three-dimensional phonons. Using the bond-mean-field theory, we show…
We investigate the single-site von Neumann entropy along a harmonically confined superfluid chain, as described by the one-dimensional fermionic Hubbard model with strongly attractive interactions. We find that by increasing the confinement…
We study a one-dimensional electron liquid coupled by a weak spin-exchange interaction to an antiferromagnetic spin-S ladder with n legs. A perturbative renormalization group analysis in the semiclassical limit reveals the opening of a spin…
We study the Heisenberg antiferromagnetic chain with both dimerization and frustration. The classical ground state has three phases: a Neel phase, a spiral phase and a colinear phase. In each phase, we discuss a non-linear sigma model field…
The 2-leg t-J ladder forms a spin liquid at half-filling which evolves to a Luther-Emery liquid upon doping. Our aim is to obtain a complete phase diagram for isotropic coupling (i.e. rungs and legs equal) as a function of electron density…
We investigate the properties of a three-leg quantum spin tube using several techniques such as the density matrix renormalization group method, strong coupling approaches and the non linear sigma model. For integer spins S, the model…
Geometric frustration effects were studied systematically with the Ising antiferromagnet on the 11 Archimedean lattices using the Monte-Carlo methods. The Wang-Landau algorithm for static properties (specific heat and residual entropy) and…
The spin dynamics in the block magnetic phase of the iron-based ladder compound \bfs\ has been studied by means of single crystal inelastic neutron scattering. Using linear spin wave theory and Monte-Carlo simulations, our analysis points…
In this letter we extend the nonlinear sigma model describing pure spin ladders with an arbitrary number of legs to the case of ladders containing a single static hole. A simple immediate application of this approach to classical ladders is…
We discuss a one-dimensional fermionic model with a generalized $\mathbb{Z}_{N}$ even multiplet pairing extending Kitaev $\mathbb{Z}_{2}$ chain. The system shares many features with models believed to host localized edge parafermions, the…
The magnetization process of the $S=1$ antiferromagnetic chain with the single-ion anisotropy $D$ and the biquadratic interaction is investigated using the numerical diagonalization. Both interactions stabilize the 2-magnon…
In order to check whether odd-numbered Tomonaga-Luttinger ladders are dominated by antiferromagnetic correlations associated with gapless spin excitations, correlation functions of the doped three-chain Hubbard model are obtained with the…
We use the tensor network algorithm to show evidences of a non-uniform chiral spin-liquid (CSL) ground state in a frustrated spin-1/2 model on a square lattice, in the regime of moat-like band structure of the lattice, i.e., a band with…
We investigate the phase diagram of the cross-coupled Heisenberg spin ladder with antiferromagnetic couplings. For this model there have been conflicting results for the existence of the columnar dimer phase, which was predicted on the…
We propose a universal non-linear sigma model field theory for one dimensional frustrated ferromagnets, which applies in the vicinity of a "quantum Lifshitz point", at which the ferromagnetic state develops a spin wave instability. We…
We explore the ground-state phase diagram of the $S\!=\!1/2$ two-leg ladder with different isotropic leg interactions and uniform anisotropic rung ones, which is described by the Hamiltonian ${\cal H}=J_{{\rm l},a}…