Related papers: Ordered phases in spin-Peierls systems
We study the effect of spin-Peierls instability on the phase-diagram of a frustrated antiferromagnetic spin-1/2 ladder, with weak transverse and diagonal rung coupling. Our analysis focuses on a one-dimensional version of the model (i.e. a…
We present a theory of the anisotropy tuned quantum phase transition between spin nematic and spin-Peierls phases in S=1 systems with significant bi-quadratic exchange interactions. Based on quantum Monte Carlo studies on finite size…
Integrable discretizations are introduced for the rational and hyperbolic spin Ruijsenaars--Schneider models. These discrete dynamical systems are demonstrated to belong to the same integrable hierarchies as their continuous--time…
I review some numerical ways to determine the parameters of systems close to a first order phase transition point: energy and specific heat of the coexisting phases and interface tension. Numerical examples are given for the 2-d $q$ states…
The validity of the adiabatic approach to spin-Peierls transitions is assessed. An alternative approach is developed which maps the initial magneto-elastic problem to an effective magnetic problem only. Thus the equivalence of…
The microscopic approach to the description of the phase behaviour and critical phenomena in binary fluid mixtures is proposed. It is based on the method of collective variables with a reference system. The physical nature of the order…
We formulate and study a spin-orbital model for a family of cubic double perovskites with $d^1$ ions occupying a frustrated fcc sublattice. A variational approach and a complimentary analytical analysis reveal a rich variety of phases…
Using inelastic magnetic neutron scattering we have discovered a localized spin resonance at 4.5 meV in the ordered phase of the geometrically frustrated cubic antiferromagnet $\rm ZnCr_2O_4$. The resonance develops abruptly from quantum…
First-order structural phase transition is a common phenomenon in materials that qualitatively alters their physical properties. Yet, the abrupt first-order nature is usually unexplained by realistic computations, implying an omission of…
We consider a lattice model of itinerant electrons coupled to an array of localized classical Heisenberg spins. The nature of the ground state ordered magnetic phases that result from the indirect spin-spin coupling mediated by the…
Topological phases are characterised by a topological invariant that remains unchanged by deformations in the Hamiltonian. Materials exhibiting topological phases include topological insulators, superconductors exhibiting strong spin-orbit…
Dynamical properties of the novel inorganic spin-Peierls compound \alpha'--NaV2O5 are investigated using a one-dimensional dimerized Heisenberg model. By exact diagonalizations of chains with up to 28 sites, supplemented by a finite-size…
Dimension reduction due to the orbital ordering has recently been proposed to explain the exotic charge, magnetic and structural transitions in some three-dimensional (3D) transitional metal oxides. We present optical measurement on a…
We propose a protocol for realizing the stripe phase in two spin models on a two-dimensional square lattice, which can be implemented with strongly magnetic atoms (Cr, Dy, Er, etc.) in optical lattices by encoding spin states into Zeeman…
We study the (spin-)Peierls transition in quasi-one-dimensional disordered systems, treating the lattice classically. The role of kinks, induced thermally and by disorder, is emphasized. For weak interchain interaction the kinks destroy the…
Due to a ferromagnetic in-chain coupling between Co$^{3+}$ ions at trigonal sites, chains Co$_2$O$_6$ are considered as large rigid spin moments. The antiferromagnetic Ising model on the triangular lattice is applied to describe an…
We consider the ground states, excitations and dynamics of a quasi-two-dimensional binary dipolar Bose-Einstein condensate. Our focus is on the transition to a spin-stripe ground state in which the translational invariance is spontaneously…
Comprehensive neutron scattering studies were carried out on a series of high-quality single crystals of Cu_{1-x}Zn_xGeO_3. The Zn concentration, x, was determined for each sample using Electron Probe Micro-Analysis. The measured Zn…
The three-state Potts model is numerically investigated on three-dimensional simple cubic lattices of up to \(128^3\) volume, concentrating on the neighborhood of the first-order phase transition separating the ordered and disordered…
We analyze a scheme for preparation of magnetically ordered states of two-component bosonic atoms in optical lattices. We compute the dynamics during adiabatic and optimized time-dependent ramps to produce ground states of effective spin…