相关论文: Combined Molecular and Spin Dynamics Simulation of…
We derive a master equation that allows us to study non-equilibrium dynamics of a quantum antiferromagnet. By resorting to spin-wave theory, we obtain a closed analytic form for the magnon decay rates. These turn out to be closely related…
Spin wave calculations demonstrate that the macroscopic continuous degeneracy associated with the two-dimensional kagome Heisenberg spin lattice persists in the case of the stacked fcc structure giving rise to zero energy modes in three…
We study the quantum spin dynamics of a frustrated XXZ model on a pyrochlore lattice by using large-scale quantum Monte Carlo simulation and stochastic analytic continuation. In the low-temperature quantum spin ice regime, we observe…
We have implemented non-collinear GGA and a generalized Bloch's theorem to simulate unconmensurate spiral arrangements of spins in a Density Functional Theory code based on localized wave functions. We have subsequently performed a thorough…
Joint influence of two effects, namely, nonequilibrium spin injection by current, and current induced surface torque, on spin-valve type ferromagnetic metallic junctions is considered theoretically. The CPP configuration is assumed. The…
Magnetic skyrmions exhibit unique, technologically relevant pseudo-particle behaviors which arise from their topological protection, including well-defined, three-dimensional dynamic modes that occur at microwave frequencies. During dynamic…
The magnetization dynamics induced by standing elastic waves excited in a thin ferromagnetic film is described with the aid of micromagnetic simulations taking into account the magnetoelastic coupling between spins and lattice strains. The…
We compute lattice dynamical properties of iron at the bcc-fcc phase transition using dynamical mean-field theory implemented with the frozen-phonon method. Electronic correlations are found to have a strong effect on the lattice stability…
Recent results from the UKQCD Collaboration's dynamical simulations are presented. The main feature of these ensembles is that they have a fixed lattice spacing and volume, but varying sea quark mass from infinite (corresponding to the…
Surface curvature of magnetic systems can lead to many static and dynamic effects which are not present in flat systems of the same material. These emergent magnetochiral effects can lead to frequency nonreciprocity of spin waves, which has…
In quantum magnetic materials it is common to observe both static and dynamic lattice effects on the magnetic excitation spectrum. Less common is to find that the magnetic correlations have a significant impact on the phonon spectrum. Can…
We investigate the spin dynamics of excitons interacting with acoustic phonons in quantum wells, quantum wires and quantum disks by employing a multiband model based on the $4\times4$ Luttinger Hamiltonian. We also use the Bir-Pikus…
The two-layer square lattice quantum antiferromagnet with spins 1/2 shows a zero-field magnetic order-disorder transition at a critical ratio of the inter-plane to intra-plane couplings. Adding a uniform magnetic field tunes the system to…
The electron-excitation induced bond strength variations in metals have been predicted from density-functional theory calculations and observed experimentally, while the microscopic mechanism has yet to be elucidated. Here, we present a…
We present a computational scheme to study spin excitations in magnetic materials from first principles. The central quantity is the transverse spin susceptibility, from which the complete excitation spectrum, including single-particle…
Large-scale simulations of the spin dynamics in quantum dots subjected to trains of periodic laser pulses enable us to describe and understand related experiments. By comparing the data for different models to experimental results, we gain…
The total angular momentum of a close system is a conserved quantity, which should remain constant in time for any excitation experiment once the pumping signal has extinguished. Such conservation, however, is never satisfied in practice in…
Recent neutron scattering experiments have revealed that the generic form of the magnetic excitations in the high-Tc cuprates of wide range of doping has the so-called "hourglass" shape; it features both upward and downward excitations at…
We use spin-lattice dynamics simulations to study the possibility of modeling the magnetic hysteresis behavior of a ferromagnetic material. The temporal evolution of the magnetic and mechanical degrees of freedom is obtained through a set…
We use general hydrodynamic equations to determine the long-wavelength spin excitations in isotropic antiferromagnets in the presence of a homogeneous magnetization. The latter may be induced, such as in antiferromagnets in an external…