Related papers: Quasi-static strain governing ultrafast spin dynam…
The dynamics and the thermodynamics of particles/spins interacting via long-range forces display several unusual features with respect to systems with short-range interactions. The Hamiltonian Mean Field (HMF) model, a Hamiltonian system of…
We investigate the microwave spin excitations of the cubic chiral magnet Fe$_{0.75}$Co$_{0.25}$Si as driven by the thermal modulation of magnetic interactions via laser heating and probed by time-resolved measurements of the magneto-optical…
Motivated by recent experimental progress in the quasi-one-dimensional quantum magnet NiNb$_2$O$_6$, we study the spin dynamics of an S=1 ferromagnetic Heisenberg chain with single-ion anisotropy by using a semiclassical molecular dynamics…
Quantum spin liquids (QSLs) host exotic fractionalized magnetic and gauge-field excitations whose microscopic origins and experimental verification remain frustratingly elusive. In the absence of static magnetic order, the spin excitation…
We study the effects of quantum fluctuations and the excitation spectrum for the antiferromagnetic Heisenberg model on a two-dimensional quasicrystal, by numerically solving linear spin-wave theory on finite approximants of the octagonal…
The dynamical spin susceptibility is studied in the magnetically-disordered phase of heavy-Fermion systems near the antiferromagnetic quantum phase transition. In the framework of the $S=1/2$ Kondo lattice model, we introduce a perturbative…
Femtosecond (fs)-resolved simultaneous measurements of charge and spin dynamics reveal the coexistence of two different quasi-particle excitations in colossal magneto-resistive (CMR) manganites, with {\em fs} and {\em ps} relaxation times…
Quasiparticles are physically motivated mathematical constructs for simplifying the seemingly complicated many-body description of solids. A complete understanding of their dynamics and the nature of the effective interactions between them…
Time-resolved magneto-optical Kerr spectroscopy of ferromagnetic InMnAs reveals two distinct {\em demagnetization} processes -- fast ($<1$ ps) and slow ($\sim$100 ps). Both components diminish with increasing temperature and are absent…
Systems with long-range interactions (LRI) display unusual thermodynamical and dynamical properties that stem from the non-additive character of the interaction potential. We focus in this work on the lack of relaxation to thermal…
We study conditions of the appearance of $U(1)\times \mathbb{Z}_2$ superconducting states that spontaneously break time-reversal symmetry (BTRS) on a square lattice as a function of applied stress. Calculations show that if critical…
We show that long-range ferromagnetic interactions in quantum spin chains can induce spatial quasi-localization of topological magnetic defects, i.e., domain-walls, even in the absence of quenched disorder. By means of matrix-product-states…
We consider the thermodynamic properties of the quasi-two-dimensional spin-half Heisenberg ferromagnet on the stacked square and the stacked kagom\'e lattices by using the spin-rotation-invariant Green's function method. We calculate the…
Through an extended kinetic model, we study the nonlinear generation of quasi-static magnetic fields by high-frequency fields in a plasma, taking into account the effects of the electron spin. It is found that although the largest part of…
Several observed transport and thermodynamic properties of the heavy-fermion compound YbRh2Si2 in the quantum critical regime are unusual and suggest that the fermionic quasiparticles are critical, characterized by a scale-dependent…
Ultrafast optical excitation is known to destabilize long-range order in correlated systems, yet experiments have also reported the emergence of metastable phases, in some cases with enhanced critical temperatures. The microscopic origin of…
Unveiling the key mechanisms that determine optically driven spin dynamics is essential both to probe the fundamental nature of ultrafast light-matter interactions, but also to drive future technologies of smaller, faster, and more energy…
Initially far out-of-equilibrium self-gravitating systems form, through a collisionless relaxation dynamics, quasi-stationary states (QSS). These may arise from a bottom-up aggregation of structures or in a top-down frame; their…
In a quantum spin liquid, the magnetic moments of the constituent electron spins evade classical long-range order to form an exotic state that is quantum entangled and coherent over macroscopic length scales [1-2]. Such phases offer…
In this paper we have studied analytically and numerically dynamics of spin crossover induced by time-dependent pressure. We show that quasi static pressure, with a slow dependence on time, yields a spin crossover leading to transition from…