Related papers: Modulated Phases in Spin-Peierls Systems
We have studied the time evolution of magnetization of a high spin magnetic cluster in the ground state, in the presence of a sinusoidal axial magnetic field and a static transverse field by explicitly solving time dependent schr\"odinger…
This paper discusses the combined effects of optical excitation power, interface roughness, lattice temperature, and applied magnetic fields on the spin-coherence of excitonic states in GaAs/AlGaAs multiple quantum wells. For low optical…
The introduction of modified bond-defects in spin-Peierls systems is investigated in a model of antiferromagnetic Heisenberg spin chains coupled to adiabatic phonons. Generically, new low-energy magnetic or non-magnetic excitations appear…
The magnetic properties and Mott transition of the Hubbard model on the square lattice with frustration are studied at half-filling and zero temperature by the variational cluster approximation. When the on-site repulsion $U$ is large,…
We provide an analytic study of the dynamics of semiconductor lasers with injection (pump) of spin-polarized electrons, previously considered in the steady-state regime. Using complementary approaches of quasi-static and small signal…
Mutual interactions in many-body systems bring about a variety of exotic phases, among which liquid-like states failing to order due to frustration are of keen interest. Recently, an organic system with an anisotropic triangular lattice of…
We propose an optical lattice setup to investigate spin chains and ladders. Electric and magnetic fields allow us to vary at will the coupling constants, producing a variety of quantum phases including the Haldane phase, critical phases,…
The microscopic description of spin-Peierls substances is discussed. Particular attention is paid to the ordered (dimerised and incommensurably modulated) phases. Important points are the adiabatic and the antiadiabatic approach, generic…
We study the decoherence of a spin-1/2 induced by an environment which is on the verge of a continuous phase transition. We consider spin environments described by the ferromagnetic and antiferromagnetic Heisenberg models on a square…
Topological boundary modes, a hallmark of quantum topological phases, remarkably occur in classical mechanical systems through an interesting correspondence with the quantum case. Here, we explore the Maxwell lattice frustrated Mott…
The effect of interactions near the coincidence of two Landau levels with opposite spins at filling factor 1/2 is investigated. By mapping to Composite Fermions it is shown that the fluctuations of the gauge field induces an effective…
We study spin-1 bosons in an optical lattice under a magnetic field by the Gutzwiller approximation. Our results thus obtained join the discontinuous phase boundary curves obtained by perturbative studies through a first-order transition.…
A systematic treatment of the magnetic fluctuations effect on the properties of the normal-to-superconducting phase transition in a zero external magnetic field is given within the self-consistent approximation and the quasi-macroscopic…
The effect of strong magnetic fields on the properties of the pasta structures is calculated within a Thomas Fermi approach using relativistic mean field models to modulate stellar matter. It is shown how quantities such as the size of the…
We consider the quantum spin-$s$ $XXZ$ Heisenberg antiferromagnet on the two- and three-dimensional pyrochlore lattices and examine a spin-Peierls mechanism of lowering the total energy by a lattice distortion in a high magnetic field. For…
We study the dynamic phase transition properties for the mixed spin-(1/2, 1) Ising model on a square lattice under a time-dependent magnetic field by means the effective-field theory (EFT) based on the Glauber dynamics. We present the…
We study the magnetic phase diagram of spin-3/2 fermions in a spatially anisotropic square optical lattice at quarter filling (corresponding to one particle per lattice site). In the limit of the large on-site repulsion the system can be…
We study the spin wave in the S=1/2 multiple-spin exchange model on a triangular lattice in a magnetic field within the linear spin-wave theory. We take only two-, three- and four-spin exchange interactions into account and restrict…
We present a theoretical analysis of the phase diagram of two--component bosons on an optical lattice. A new formalism is developed which treats the effective spin interactions in the Mott and superfluid phases on the same footing. Using…
The magnetic stability of {\delta}-plutonium is analyzed taking into account zero-point spin fluctuations. Within the generalized theory of spin fluctuations described within a simple phenomenological model neglecting its spatial dispersion…