Related papers: $ab$-$initio$ Approaches for Low-Energy Spin Hamil…
We consider Mott insulators driven by periodic coherent laser radiation, using both single orbital and multi-orbital models, noting that the latter is of more interest in solid state systems. We derive general expressions for the resulting…
Electronic correlations in the ground state of an idealized infinite-layer high-Tc compound are computed using the ab-initio method of local ansatz. Comparisons are made with the local-density approximation (LDA) results, and the…
Recently, there has been an increasing interest in modelling and computation of physical systems with neural networks. Hamiltonian systems are an elegant and compact formalism in classical mechanics, where the dynamics is fully determined…
Coupling constants for the most relevant terms in the low energy effective Hamiltonian of the XXZ spin chain are derived. Using this result we study the low energy (low temperature, weak magnetic field) thermodynamics, finite size effects…
We propose a spin transport experiment to measure the low-energy excitations in insulators with spin degrees of freedom, with a focus on detecting ground states that lack magnetic order. A general formalism to compute the spin-current from…
A remarkable discovery in recent years is that there exist various kinds of topological insulators and superconductors characterized by a periodic table according to the system symmetry and dimensionality. To physically realize these…
Photonic solvers that are able to find the ground states of different spin Hamiltonians can be used to study many interactive physical systems and combinatorial optimization problems. Here, we establish a real-and-momentum space…
This contribution summarises the theoretical basics for the theory of x-ray matter interaction and is based on a quantised description of the electromagnetic field. In view of a formally transparent presentation, we adopt the approach of…
Using first-principles electronic structure calculations based on the Nth order muffin tin orbital (NMTO)-downfolding technique, we derived the low-energy spin model for CuTe2O5. Our study reveals that this compound is a 2D coupled…
We formulate an ab initio downfolding scheme for electron-phonon coupled systems. In this scheme, we calculate partially renormalized phonon frequencies and electron-phonon coupling, which include the screening effects of high-energy…
Owing to the unique features of low Gilbert damping, long spin-diffusion lengths and zero Ohmic losses, magnetic insulators are promising candidate materials for next-generation spintronic applications. However, due to the localized…
We consider 1D lattices described by Hubbard or Bose-Hubbard models, in the presence of periodic high-frequency perturbations, such as uniform ac force or modulation of hopping coefficients. Effective Hamiltonians for interacting particles…
The magnetic field opens a gap in the edge state spectrum of two-dimensional topological insulators thereby destroying protection of these states against backscattering. To relate properties of this gap to parameters of the system and to…
We report first-principles all-electron density-functional based studies of the electronic structure, magnetic ordering and anisotropy for the V$_{15}$ molecular magnet. From these calculations, we determine a Heisenberg Hamiltonian with…
We present a computationally efficient general first-principles based method for spin-lattice simulations for solids. Our method is based on a combination of atomistic spin dynamics and molecular dynamics, expressed through a spin-lattice…
Within the post Newtonian framework the fully reduced Hamiltonian (i.e., with eliminated spin supplementary condition) for the next-to-leading order spin-squared dynamics of general compact binaries is presented. The Hamiltonian is…
Time-dependent spin phenomena in condensed matter are most often either described in the weakly correlated limit of metallic Stoner/Slater-like magnetism via band theory or in the strongly correlated limit of Heisenberg-like interacting…
In the last decades, collinear magnetic insulating systems have emerged as promising energy-saving information carriers. Their elementary collective spin excitations, i.e., magnons, can propagate for long distances bypassing the Joule…
This article aims at giving a general presentation of spintronics, an important field of research developing today along many new directions in physics of condensed matter. We tried to present simply the physical phenomena involved in…
We study the magnetic properties of the adatom systems on a semiconductor surface Si(111):\{C,Si,Sn,Pb\} - ($\sqrt{3} \times \sqrt{3}$). On the basis of all-electron density functional theory calculations we construct effective low-energy…