publicationDate stringlengths 1 2.79k | title stringlengths 1 36.5k ⌀ | abstract stringlengths 1 37.3k ⌀ | id stringlengths 9 47 |
|---|---|---|---|
2023-05-23 | Current-driven motion of magnetic topological defects in ferromagnetic superconductors | Recent years have seen a number of instances where magnetism and
superconductivity intrinsically coexist. Our focus is on the case where
spin-triplet superconductivity arises out of ferromagnetism, and we make a
hydrodynamic analysis of the effect of a charge supercurrent on magnetic
topological defects like domain wal... | 2305.13564v1 |
2023-07-03 | Magnetic lump motion in saturated ferromagnetic films | In this paper, we study in detail the nonlinear propagation of magnetic
soliton in a ferromagnetic film. The sample is magnetized to saturation by an
external field perpendicular to film plane. A new generalized (2+1)-dimensional
short-wave asymptotic model is derived. The bilinear-like forms of this
equation are const... | 2307.00903v1 |
2005-03-24 | Fast magnetization switching of Stoner particles: A nonlinear dynamics picture | The magnetization reversal of Stoner particles is investigated from the point
of view of nonlinear dynamics within the Landau-Lifshitz-Gilbert formulation.
The following results are obtained. 1) We clarify that the so-called
Stoner-Wohlfarth (SW) limit becomes exact when damping constant is infinitely
large. Under the ... | 0503594v1 |
2022-03-03 | Stability results of locally coupled wave equations with local Kelvin-Voigt damping: Cases when the supports of damping and coupling coefficients are disjoint | In this paper, we study the direct/indirect stability of locally coupled wave
equations with local Kelvin-Voigt dampings/damping and by assuming that the
supports of the dampings and the coupling coefficients are disjoint. First, we
prove the well-posedness, strong stability, and polynomial stability for some
one dimen... | 2203.01632v1 |
2020-09-16 | Fast convex optimization via inertial dynamics combining viscous and Hessian-driven damping with time rescaling | In a Hilbert setting, we develop fast methods for convex unconstrained
optimization. We rely on the asymptotic behavior of an inertial system
combining geometric damping with temporal scaling. The convex function to
minimize enters the dynamic via its gradient. The dynamic includes three
coefficients varying with time,... | 2009.07620v1 |
2021-08-04 | Nonlinear fluid damping of elastically mounted pitching wings in quiescent water | We experimentally study the nonlinear fluid damping of a rigid but
elastically mounted pitching wing in the absence of a freestream flow. The
dynamics of the elastic mount are simulated using a cyber-physical system. We
perturb the wing and measure the fluid damping coefficient from damped
oscillations over a large ran... | 2108.02090v1 |
2023-07-05 | Optimal damping of vibrating systems: dependence on initial conditions | Common criteria used for measuring performance of vibrating systems have one
thing in common: they do not depend on initial conditions of the system. In
some cases it is assumed that the system has zero initial conditions, or some
kind of averaging is used to get rid of initial conditions. The aim of this
paper is to i... | 2307.02352v2 |
2021-06-25 | Perturbed primal-dual dynamics with damping and time scaling coefficients for affine constrained convex optimization problems | In Hilbert space, we propose a family of primal-dual dynamical system for
affine constrained convex optimization problem. Several damping coefficients,
time scaling coefficients, and perturbation terms are thus considered. By
constructing the energy functions, we investigate the convergence rates with
different choices... | 2106.13702v1 |
2020-06-24 | Stability of a star-shaped network with local Kelvin-Voigt damping and non-smooth coefficient at interface | In this paper, we study the stability problem of a star-shaped network of
elastic strings with a local Kelvin-Voigt damping. Under the assumption that
the damping coefficients have some singularities near the transmission point,
we prove that the semigroup corresponding to the system is polynomially stable
and the deca... | 2006.14949v1 |
2008-05-07 | Comparison Between Damping Coefficients of Measured Perforated Micromechanical Test Structures and Compact Models | Measured damping coefficients of six different perforated micromechanical
test structures are compared with damping coefficients given by published
compact models. The motion of the perforated plates is almost translational,
the surface shape is rectangular, and the perforation is uniform validating the
assumptions mad... | 0805.0893v1 |
2003-02-17 | Magnetization dynamics with a spin-transfer torque | The magnetization reversal and dynamics of a spin valve pillar, whose lateral
size is 64$\times$64 nm$^2$, are studied by using micromagnetic simulation in
the presence of spin transfer torque. Spin torques display both characteristics
of magnetic damping (or anti-damping) and of an effective magnetic field. For a
stea... | 0302337v1 |
2003-10-13 | Domain wall mobility in nanowires: transverse versus vortex walls | The motion of domain walls in ferromagnetic, cylindrical nanowires is
investigated numerically by solving the Landau-Lifshitz-Gilbert equation for a
classical spin model in which energy contributions from exchange, crystalline
anisotropy, dipole-dipole interaction, and a driving magnetic field are
considered. Depending... | 0310277v1 |
2013-10-29 | Observational Study of Large Amplitude Longitudinal Oscillations in a Solar Filament | On 20 August 2010 an energetic disturbance triggered damped large-amplitude
longitudinal (LAL) oscillations in almost an entire filament. In the present
work we analyze this periodic motion in the filament to characterize the
damping and restoring mechanism of the oscillation. Our method involves placing
slits along th... | 1310.7657v1 |
2014-12-08 | Magnetization Dynamics driven by Non-equilibrium Spin-Orbit Coupled Electron Gas | The dynamics of magnetization coupled to an electron gas via s-d exchange
interaction is investigated by using density matrix technique. Our theory shows
that non-equilibrium spin accumulation induces a spin torque and the electron
bath leads to a damping of the magnetization. For the two-dimensional
magnetization thin... | 1412.2479v1 |
2017-03-06 | Damping dependence of spin-torque effects in thermally assisted magnetization reversal | Thermal fluctuations of nanomagnets driven by spin-polarized currents are
treated via the Landau-Lifshitz-Gilbert equation as generalized to include both
the random thermal noise field and Slonczewski spin-transfer torque terms. The
magnetization reversal time of such a nanomagnet is then evaluated for wide
ranges of d... | 1703.01879v5 |
2017-05-09 | Low spin wave damping in the insulating chiral magnet Cu$_{2}$OSeO$_{3}$ | Chiral magnets with topologically nontrivial spin order such as Skyrmions
have generated enormous interest in both fundamental and applied sciences. We
report broadband microwave spectroscopy performed on the insulating chiral
ferrimagnet Cu$_{2}$OSeO$_{3}$. For the damping of magnetization dynamics we
find a remarkabl... | 1705.03416v1 |
2018-09-04 | Separation of the two-magnon scattering contribution to damping for the determination of the spin mixing conductance | We present angle dependent measurements of the damping properties of
epitaxial Fe layers with MgO, Al and Pt capping layers. Based on the
preferential distribution of lattice defects following the crystal symmetry, we
make use of a model of the defect density to separate the contribution of
two-magnon scattering to the... | 1809.01042v1 |
2011-11-27 | A two-stage approach to relaxation in billiard systems of locally confined hard spheres | We consider the three-dimensional dynamics of systems of many interacting
hard spheres, each individually confined to a dispersive environment, and show
that the macroscopic limit of such systems is characterized by a coefficient of
heat conduction whose value reduces to a dimensional formula in the limit of
vanishingl... | 1111.6272v1 |
2014-03-16 | Interpolating local constants in families | We extend the theory of local constants to l-adic families of representations
of GL_n(F) where F is a p-adic field with l not equal to p. We construct zeta
integrals and gamma factors for representations coming from the conjectural
"local Langlands correspondence in families" of Emerton-Helm, proving a
rationality resu... | 1403.3914v2 |
2014-08-02 | Machta-Zwanzig regime of anomalous diffusion in infinite-horizon billiards | We study diffusion on a periodic billiard table with infinite horizon in the
limit of narrow corridors. An effective trapping mechanism emerges according to
which the process can be modeled by a L\'evy walk combining
exponentially-distributed trapping times with free propagation along paths
whose precise probabilities ... | 1408.0349v1 |
2022-12-22 | Novel Bottomonium Results | We present the latest results from the use of the Backus-Gilbert method for
reconstructing the spectra of NRQCD bottomonium mesons using anisotropic
FASTSUM ensembles at non-zero temperature. We focus in particular on results
from the $\eta_b$, $\Upsilon$, $\chi_{b1}$ and $h_b$ generated from
Tikhonov-regularized Backu... | 2212.12016v1 |
2023-11-29 | Bayesian interpretation of Backus-Gilbert methods | The extraction of spectral densities from Euclidean correlators evaluated on
the lattice is an important problem, as these quantities encode physical
information on scattering amplitudes, finite-volume spectra, inclusive decay
rates, and transport coefficients. In this contribution, we show that the
Bayesian approach t... | 2311.18125v1 |
2006-02-09 | Magnetization damping in polycrystalline Co ultra-thin films: Evidence for non-local effects | The magnetic properties and magnetization dynamics of polycrystalline
ultra-thin Co layers were investigated using a broadband ferromagnetic
resonance (FMR) technique at room temperature. A variable thickness (1 nm $\leq
t \leq$ 10 nm) Co layer is sandwiched between 10 nm thick Cu layers (10 nm Cu|
t Co|10 nm Cu), whil... | 0602243v2 |
2020-04-09 | Magnetic Damping in Epitaxial Fe Alloyed with Vanadium and Aluminum | To develop low-moment, low-damping metallic ferromagnets for power-efficient
spintronic devices, it is crucial to understand how magnetic relaxation is
impacted by the addition of nonmagnetic elements. Here, we compare magnetic
relaxation in epitaxial Fe films alloyed with light nonmagnetic elements of V
and Al. FeV al... | 2004.04840v3 |
2016-05-17 | Simultaneous Identification of Damping Coefficient and Initial Value in PDEs from boundary measurement | In this paper, the simultaneous identification of damping or anti-damping
coefficient and initial value for some PDEs is considered. An identification
algorithm is proposed based on the fact that the output of system happens to be
decomposed into a product of an exponential function and a periodic function.
The former ... | 1605.05063v1 |
2020-03-13 | Anharmonic phonon damping enhances the $T_c$ of BCS-type superconductors | A theory of superconductivity is presented where the effect of anharmonicity,
as entailed in the acoustic, or optical, phonon damping, is explicitly
considered in the pairing mechanism. The gap equation is solved including
diffusive Akhiezer damping for longitudinal acoustic phonons or Klemens damping
for optical phono... | 2003.06220v2 |
2014-05-19 | Comparison of micromagnetic parameters of ferromagnetic semiconductors (Ga,Mn)(As,P) and (Ga,Mn)As | We report on the determination of micromagnetic parameters of epilayers of
the ferromagnetic semiconductor (Ga,Mn)As, which has easy axis in the sample
plane, and (Ga,Mn)(As,P) which has easy axis perpendicular to the sample plane.
We use an optical analog of ferromagnetic resonance where the
laser-pulse-induced preces... | 1405.4677v1 |
2015-03-24 | Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure | Perpendicular magnetic anisotropy (PMA) and low magnetic damping are the key
factors for the free layer magnetization switching by spin transfer torque
technique in magnetic tunnel junction devices. The magnetization precessional
dynamics in soft ferromagnetic FeTaC thin film with a stripe domain structure
was explored... | 1503.07043v5 |
2016-05-22 | Low Gilbert damping in Co2FeSi and Fe2CoSi films | Thin highly textured Fe$_{\mathrm{1+x}}$Co$_{\mathrm{2-x}}$Si ($0 \leq$ x
$\leq 1$) films were prepared on MgO (001) substrates by magnetron
co-sputtering. The magneto-optic Kerr effect (MOKE) and ferromagnetic resonance
(FMR) measurements were used to investigate the composition dependence of the
magnetization, the ma... | 1605.06797v1 |
2017-09-21 | Low Gilbert Damping Constant in Perpendicularly Magnetized W/CoFeB/MgO Films with High Thermal Stability | Perpendicular magnetic materials with low damping constant and high thermal
stability have great potential for realizing high-density, non-volatile, and
low-power consumption spintronic devices, which can sustain operation
reliability for high processing temperatures. In this work, we study the
Gilbert damping constant... | 1709.07483v1 |
2022-02-06 | Enhancing Perpendicular Magnetic Anisotropy in Garnet Ferrimagnet by Interfacing with Few-Layer WTe2 | Engineering magnetic anisotropy in a ferro- or ferrimagnetic (FM) thin film
is crucial in spintronic device. One way to modify the magnetic anisotropy is
through the surface of the FM thin film. Here, we report the emergence of a
perpendicular magnetic anisotropy (PMA) induced by interfacial interactions in
a heterostr... | 2202.02834v1 |
2022-05-27 | Scalar field damping at high temperatures | The motion of a scalar field that interacts with a hot plasma, like the
inflaton during reheating, is damped, which is a dissipative process. At high
temperatures the damping can be described by a local term in the effective
equation of motion. The damping coefficient is sensitive to multiple
scattering. In the loop ex... | 2205.14166v2 |
2022-12-02 | Equivalence between the energy decay of fractional damped Klein-Gordon equations and geometric conditions for damping coefficients | We consider damped $s$-fractional Klein--Gordon equations on $\mathbb{R}^d$,
where $s$ denotes the order of the fractional Laplacian. In the one-dimensional
case $d = 1$, Green (2020) established that the exponential decay for $s \geq
2$ and the polynomial decay of order $s/(4-2s)$ hold if and only if the damping
coeff... | 2212.01029v4 |
2017-06-13 | Uniform energy decay for wave equations with unbounded damping coefficients | We consider the Cauchy problem for wave equations with unbounded damping
coefficients in the whole space. For a general class of unbounded damping
coefficients, we derive uniform total energy decay estimates together with a
unique existence result of a weak solution. In this case we never impose strong
assumptions such... | 1706.03942v1 |
2021-06-09 | Grammage of cosmic rays in the proximity of supernova remnants embedded in a partially ionized medium | We investigate the damping of Alfv\'en waves generated by the cosmic ray
resonant streaming instability in the context of the cosmic ray escape and
propagation in the proximity of supernova remnants. We consider ion-neutral
damping, turbulent damping and non linear Landau damping in the warm ionized
and warm neutral ph... | 2106.04948v1 |
2023-02-23 | Buckling Metamaterials for Extreme Vibration Damping | Damping mechanical resonances is a formidable challenge in an increasing
number of applications. Many of the passive damping methods rely on using low
stiffness dissipative elements, complex mechanical structures or electrical
systems, while active vibration damping systems typically add an additional
layer of complexi... | 2302.11968v1 |
2014-03-19 | The effects of time-dependent dissipation on the basins of attraction for the pendulum with oscillating support | We consider a pendulum with vertically oscillating support and time-dependent
damping coefficient which varies until reaching a finite final value. The sizes
of the corresponding basins of attraction are found to depend strongly on the
full evolution of the dissipation. In order to predict the behaviour of the
system, ... | 1403.4996v1 |
2016-08-14 | Mechanical energy and mean equivalent viscous damping for SDOF fractional oscillators | This paper addresses the total mechanical energy of a single degree of
freedom fractional oscillator. Based on the energy storage and dissipation
properties of the Caputo fractional derivatives, the expression for total
mechanical energy in the single degree of freedom fractional oscillator is
firstly presented. The en... | 1608.04071v1 |
2023-09-26 | Qualitative properties of solutions to a nonlinear transmission problem for an elastic Bresse beam | We consider a nonlinear transmission problem for a Bresse beam, which
consists of two parts, damped and undamped. The mechanical damping in the
damped part is present in the shear angle equation only, and the damped part
may be of arbitrary positive length. We prove well-posedness of the
corresponding PDE system in ene... | 2309.15171v2 |
2016-09-05 | Remarks on an elliptic problem arising in weighted energy estimates for wave equations with space-dependent damping term in an exterior domain | This paper is concerned with weighted energy estimates and diffusion
phenomena for the initial-boundary problem of the wave equation with
space-dependent damping term in an exterior domain. In this analysis, an
elliptic problem was introduced by Todorova and Yordanov. This attempt was
quite useful when the coefficient ... | 1609.01063v2 |
2017-03-09 | Long-time dynamics of the strongly damped semilinear plate equation in $\mathbb{R}^{n}$ | We investigate the initial-value problem for the semilinear plate equation
containing localized strong damping, localized weak damping and nonlocal
nonlinearity. We prove that if nonnegative damping coefficients are strictly
positive almost everywhere in the exterior of some ball and the sum of these
coefficients is po... | 1703.03485v2 |
2020-11-06 | A generalized finite element method for the strongly damped wave equation with rapidly varying data | We propose a generalized finite element method for the strongly damped wave
equation with highly varying coefficients. The proposed method is based on the
localized orthogonal decomposition introduced and is designed to handle
independent variations in both the damping and the wave propagation speed
respectively. The m... | 2011.03311v1 |
2022-10-30 | Intrinsic polynomial squeezing for Balakrishnan-Taylor beam models | We explore the energy decay properties related to a model in extensible beams
with the so-called energy damping. We investigate the influence of the
nonloncal damping coefficient in the stability of the model. We prove, for the
first time, that the corresponding energy functional is squeezed by
polynomial-like function... | 2210.16931v1 |
2020-11-16 | Technology to Counter Online Flaming Based on the Frequency-Dependent Damping Coefficient in the Oscillation Model | Online social networks, which are remarkably active, often experience
explosive user dynamics such as online flaming, which can significantly impact
the real world. However, countermeasures based on social analyses of the
individuals causing flaming are too slow to be effective because of the
rapidity with which the in... | 2011.08117v1 |
2018-10-25 | Time-retarded damping and magnetic inertia in the Landau-Lifshitz-Gilbert equation self-consistently coupled to electronic time-dependent nonequilibrium Green functions | The conventional Landau-Lifshitz-Gilbert (LLG) equation is a widely used tool
to describe dynamics of local magnetic moments, viewed as classical vectors of
fixed length, with their change assumed to take place simultaneously with the
cause. Here we demonstrate that recently developed [M. D. Petrovi\'{c} {\em et
al.}, ... | 1810.11016v2 |
2019-08-08 | Annihilation of topological solitons in magnetism with spin wave burst finale: The role of nonequilibrium electrons causing nonlocal damping and spin pumping over ultrabroadband frequency range | We not only reproduce burst of short-wavelength spin waves (SWs) observed in
recent experiment [S. Woo et al., Nat. Phys. 13, 448 (2017)] on
magnetic-field-driven annihilation of two magnetic domain walls (DWs) but,
furthermore, we predict that this setup additionally generates highly unusual}
pumping of electronic spi... | 1908.03194v5 |
2020-09-23 | Remark on the exponential decay of the solutions of the damped wave equation | A condition which guaranties the exponential decay of the solutions of the
initial-boundary value problem for the damped wave equation is proved. A method
for the effective computability of the coefficient of exponential decay is also
presented. | 2009.11244v1 |
2021-06-22 | Choice of Damping Coefficient in Langevin Dynamics | This article considers the application of Langevin dynamics to sampling and
investigates how to choose the damping parameter in Langevin dynamics for the
purpose of maximizing thoroughness of sampling. Also, it considers the
computation of measures of sampling thoroughness. | 2106.11597v1 |
2004-03-12 | Factorization of damped wave equations with cubic nonlinearities | The recent factorization scheme that we introduced for nonlinear polynomial
ODEs in math-ph/0401040 is applied to the interesting case of damped wave
equations with cubic nonlinearities. Traveling kink solutions are possible in
the plane defined by the kink velocity versus the damping coefficient only
along hyperbolas ... | 0403022v1 |
2002-08-07 | Toward a Universal Model of Damping--Modified Coulomb Friction | A modification of Coulomb's law of friction uses a variable coefficient of
friction that depends on a power law in the energy of mechanical oscillation.
Through the use of three different exponents: 0, 1/2 and 1; all commonly
encountered non-viscous forms of damping are accommodated. The nonlinear model
appears to yiel... | 0208025v1 |
2012-12-08 | A note on the lifespan of solutions to the semilinear damped wave equation | This paper concerns estimates of the lifespan of solutions to the semilinear
damped wave equation. We give upper estimates of the lifespan for the
semilinear damped wave equation with variable coefficients in all space
dimensions. | 1212.1772v3 |
2018-03-20 | Stability of the wave equations on a tree with local Kelvin-Voigt damping | In this paper we study the stability problem of a tree of elastic strings
with local Kelvin-Voigt damping on some of the edges. Under the compatibility
condition of displacement and strain and continuity condition of damping
coefficients at the vertices of the tree, exponential/polynomial stability are
proved. | 1803.07280v1 |
2021-08-17 | Spectral enclosures for the damped elastic wave equation | In this paper we investigate spectral properties of the damped elastic wave
equation. Deducing a correspondence between the eigenvalue problem of this
model and the one of Lam\'e operators with non self-adjoint perturbations, we
provide quantitative bounds on the location of the point spectrum in terms of
suitable norm... | 2108.07676v1 |
2022-05-26 | Ergodic results for the stochastic nonlinear Schrödinger equation with large damping | We study the nonlinear Schr\"odinger equation with linear damping, i.e. a
zero order dissipation, and additive noise. Working in $R^d$ with d = 2 or d =
3, we prove the uniqueness of the invariant measure when the damping
coefficient is sufficiently large. | 2205.13364v1 |
2016-08-30 | Optimal damping ratios of multi-axial perfectly matched layers for elastic-wave modeling in general anisotropic media | The conventional Perfectly Matched Layer (PML) is unstable for certain kinds
of anisotropic media. This instability is intrinsic and independent of PML
formulation or implementation. The Multi-axial PML (MPML) removes such
instability using a nonzero damping coefficient in the direction parallel with
the interface betw... | 1608.08326v3 |
2017-10-13 | Mode-Dependent Damping in Metallic Antiferromagnets Due to Inter-Sublattice Spin Pumping | Damping in magnetization dynamics characterizes the dissipation of magnetic
energy and is essential for improving the performance of spintronics-based
devices. While the damping of ferromagnets has been well studied and can be
artificially controlled in practice, the damping parameters of
antiferromagnetic materials ar... | 1710.04766v1 |
2020-03-29 | Stability results for an elastic-viscoelastic waves interaction systems with localized Kelvin-Voigt damping and with an internal or boundary time delay | We investigate the stability of a one-dimensional wave equation with non
smooth localized internal viscoelastic damping of Kelvin-Voigt type and with
boundary or localized internal delay feedback. The main novelty in this paper
is that the Kelvin-Voigt and the delay damping are both localized via non
smooth coefficient... | 2003.12967v1 |
2023-09-15 | On the formation of singularities for the slightly supercritical NLS equation with nonlinear damping | We consider the focusing, mass-supercritical NLS equation augmented with a
nonlinear damping term. We provide sufficient conditions on the nonlinearity
exponents and damping coefficients for finite-time blow-up. In particular,
singularities are formed for focusing and dissipative nonlinearities of the
same power, provi... | 2309.08281v1 |
2006-06-05 | Phenomenological theory of current driven exchange switching in ferromagnetic nanojunctions | Phenomenological approach is developed in the theory of spin-valve type
ferromagnetic junctions to describe exchange switching by current flowing
perpendicular to interfaces. Forward and backward current switching effects are
described and they may be principally different in nature. Mobile electron
spins are considere... | 0606102v2 |
2015-07-29 | Spin dynamics and relaxation in the classical-spin Kondo-impurity model beyond the Landau-Lifschitz-Gilbert equation | The real-time dynamics of a classical spin in an external magnetic field and
locally exchange coupled to an extended one-dimensional system of
non-interacting conduction electrons is studied numerically. Retardation
effects in the coupled electron-spin dynamics are shown to be the source for
the relaxation of the spin ... | 1507.08227v2 |
2008-09-26 | Damping and magnetic anisotropy of ferromagnetic GaMnAs thin films | The magnetic properties of annealed, epitaxial Ga0.93Mn0.07As layers under
tensile and compressive stress have been investigated by X-band (9GHz) and
Q-band (35GHz) ferromagnetic resonance (FMR) spectroscopy. From the analysis of
the linewidths of the uniform mode spectra the FMR Gilbert damping factor
"alpha" has been... | 0809.4644v2 |
2013-08-02 | Spin pumping damping and magnetic proximity effect in Pd and Pt spin-sink layers | We investigated the spin pumping damping contributed by paramagnetic layers
(Pd, Pt) in both direct and indirect contact with ferromagnetic
Ni$_{81}$Fe$_{19}$ films. We find a nearly linear dependence of the
interface-related Gilbert damping enhancement $\Delta\alpha$ on the heavy-metal
spin-sink layer thicknesses t$_\... | 1308.0450v2 |
2015-02-05 | Nonlinear analysis of magnetization dynamics excited by spin Hall effect | We investigate the possibility of exciting self-oscillation in a
perpendicular ferromagnet by the spin Hall effect on the basis of a nonlinear
analysis of the Landau-Lifshitz-Gilbert (LLG) equation. In the self-oscillation
state, the energy supplied by the spin torque during a precession on a constant
energy curve shou... | 1502.01420v2 |
2015-03-04 | Critical current destabilizing perpendicular magnetization by the spin Hall effect | The critical current needed to destabilize the magnetization of a
perpendicular ferromagnet via the spin Hall effect is studied. Both the
dampinglike and fieldlike torques associated with the spin current generated by
the spin Hall effect is included in the Landau-Lifshitz-Gilbert equation to
model the system. In the a... | 1503.01478v2 |
2015-10-23 | Laser-induced THz magnetization precession for a tetragonal Heusler-like nearly compensated ferrimagnet | Laser-induced magnetization precessional dynamics was investigated in
epitaxial films of Mn$_3$Ge, which is a tetragonal Heusler-like nearly
compensated ferrimagnet. The ferromagnetic resonance (FMR) mode was observed,
the precession frequency for which exceeded 0.5 THz and originated from the
large magnetic anisotropy... | 1510.06793v1 |
2017-04-11 | CoFeAlB alloy with low damping and low magnetization for spin transfer torque switching | We investigate the effect of Al doping on the magnetic properties of the
alloy CoFeB. Comparative measurements of the saturation magnetization, the
Gilbert damping parameter $\alpha$ and the exchange constant as a function of
the annealing temperature for CoFeB and CoFeAlB thin films are presented. Our
results reveal a... | 1704.03326v1 |
2018-09-25 | Theory of damping in magnetization dynamics, dispelling a myth and pointing a way forward | There is a widely-held belief amongst theoreticians that the Gilbert damping
parameter {\alpha} in magnetization dynamics is infinite for a pure metal at
T=0. The basic error leading to this belief is pointed out explicitly and the
various methods of calculation used are viewed in a unified way based on the
Lorentzian ... | 1809.09429v1 |
2018-10-31 | Anisotropic and controllable Gilbert-Bloch dissipation in spin valves | Spin valves form a key building block in a wide range of spintronic concepts
and devices from magnetoresistive read heads to spin-transfer-torque
oscillators. We elucidate the dependence of the magnetic damping in the free
layer on the angle its equilibrium magnetization makes with that in the fixed
layer. The spin pum... | 1811.00020v2 |
2019-07-27 | Two improved Gauss-Seidel projection methods for Landau-Lifshitz-Gilbert equation | In this paper, we present two improved Gauss-Seidel projection methods with
unconditional stability. The first method updates the gyromagnetic term and the
damping term simultaneously and follows by a projection step. The second method
introduces two sets of approximate solutions, where we update the gyromagnetic
term ... | 1907.11853v1 |
2020-10-01 | Modeling coupled spin and lattice dynamics | A unified model of molecular and atomistic spin dynamics is presented
enabling simulations both in microcanonical and canonical ensembles without the
necessity of additional phenomenological spin damping. Transfer of energy and
angular momentum between the lattice and the spin systems is achieved by a
coupling term bas... | 2010.00642v1 |
2021-04-22 | Impact of Fe$_{80}$B$_{20}$ insertion on the properties of dual-MgO perpendicular magnetic tunnel junctions | We explore the impact of Fe80B20 inserted at both
Co$_{20}$Fe$_{80}$B$_{20}$/MgO interfaces of dual-MgO free layers (FLs) in
bottom-pinned magnetic tunnel junctions (MTJs). MTJ stacks are annealed for 30
min at 350 $^\circ$C and 400 $^\circ$C in a vacuum after film deposition.
Current-in-plane tunneling measurements ar... | 2104.10918v1 |
2021-09-24 | Damping in yttrium iron garnet film with an interface | We report strong damping enhancement in a 200 nm thick yttrium iron garnet
(YIG) film due to spin inhomogeneity at the interface. The growth-induced thin
interfacial gadolinium iron garnet (GdIG) layer antiferromagnetically (AFM)
exchange couples with the rest of the YIG layer. The out-of-plane angular
variation of fer... | 2109.12071v1 |
2019-01-29 | Bounding the spectral gap for an elliptic eigenvalue problem with uniformly bounded stochastic coefficients | A key quantity that occurs in the error analysis of several numerical methods
for eigenvalue problems is the distance between the eigenvalue of interest and
the next nearest eigenvalue. When we are interested in the smallest or
fundamental eigenvalue, we call this the spectral or fundamental gap. In a
recent manuscript... | 1901.10470v1 |
2003-09-11 | Theory of Current-Induced Magnetization Precession | We solve appropriate drift-diffusion and Landau-Lifshitz-Gilbert equations to
demonstrate that unpolarized current flow from a non-magnet into a ferromagnet
can produce a precession-type instability of the magnetization. The fundamental
origin of the instability is the difference in conductivity between majority
spins ... | 0309289v1 |
2005-07-20 | All-optical probe of precessional magnetization dynamics in exchange biased NiFe/FeMn bilayers | An internal anisotropy pulse field is launched by an 8.3 ps short laser
excitation, which triggers precessional magnetization dynamics of a
polycrystalline NiFe/FeMn exchange bias system on the picosecond timescale. Due
to the excitation the unidirectional anisotropy and, thus, the exchange
coupling across the interfac... | 0507475v1 |
2009-05-28 | Hydrodynamic theory of coupled current and magnetization dynamics in spin-textured ferromagnets | We develop the hydrodynamical theory of collinear spin currents coupled to
magnetization dynamics in metallic ferromagnets. The collective spin density
couples to the spin current through a U(1) Berry-phase gauge field determined
by the local texture and dynamics of the magnetization. We determine
phenomenologically th... | 0905.4544v2 |
2010-11-26 | Dependence of nonlocal Gilbert damping on the ferromagnetic layer type in FM/Cu/Pt heterostructures | We have measured the size effect in nonlocal Gilbert relaxation rate in
FM(t$_{FM}$) / Cu (5nm) [/ Pt (2nm)] / Al(2nm) heterostructures, FM = \{
Ni$_{81}$Fe$_{19}$, Co$_{60}$Fe$_{20}$B$_{20}$, pure Co\}. Common behavior is
observed for three FM layers, where the additional relaxation obeys both a
strict inverse power l... | 1011.5868v1 |
2012-06-21 | Fast domain wall propagation in uniaxial nanowires with transverse fields | Under a magnetic field along its axis, domain wall motion in a uniaxial
nanowire is much slower than in the fully anisotropic case, typically by
several orders of magnitude (the square of the dimensionless Gilbert damping
parameter). However, with the addition of a magnetic field transverse to the
wire, this behaviour ... | 1206.4819v2 |
2013-03-05 | Angle-Dependent Spin-Wave Resonance Spectroscopy of (Ga,Mn)As Films | A modeling approach for standing spin-wave resonances based on a
finite-difference formulation of the Landau-Lifshitz-Gilbert equation is
presented. In contrast to a previous study [Bihler et al., Phys. Rev. B 79,
045205 (2009)], this formalism accounts for elliptical magnetization precession
and magnetic properties ar... | 1303.1192v1 |
2013-04-26 | Landau-Lifshitz theory of the longitudinal spin Seebeck effect | Thermal-bias-induced spin angular momentum transfer between a paramagnetic
metal and ferromagnetic insulator is studied theoretically based on the
stochastic Landau-Lifshitz-Gilbert (LLG) phenomenology. Magnons in the
ferromagnet establish a nonequilibrium steady state by equilibrating with
phonons via bulk Gilbert dam... | 1304.7295v2 |
2013-09-21 | Patterns formation in axially symmetric Landau-Lifshitz-Gilbert-Slonczewski equations | The Landau-Lifshitz-Gilbert-Slonczewski equation describes magnetization
dynamics in the presence of an applied field and a spin polarized current. In
the case of axial symmetry and with focus on one space dimension, we
investigate the emergence of space-time patterns in the form of wavetrains and
coherent structures, ... | 1309.5523v4 |
2014-02-27 | On the longitudinal spin current induced by a temperature gradient in a ferromagnetic insulator | Based on the solution of the stochastic Landau-Lifshitz-Gilbert equation
discretized for a ferromagnetic chain subject to a uniform temperature
gradient, we present a detailed numerical study of the spin dynamics with a
focus particularly on finite-size effects. We calculate and analyze the net
longitudinal spin curren... | 1402.6899v1 |
2015-01-19 | Effect of Exchange Interaction on Magnetic Thermal Fluctuation and Spin Susceptibility | The expression of the thermal fluctuation parameter in the stochastic
Landau-Lifshitz-Gilbert equation has been derived from a fundamental quantum
theory of spins and phonons, in which the exchange interaction between nearest
atoms has been included. Our studies show that the thermal fluctuation
decreases exponentially... | 1501.04503v2 |
2015-07-23 | Nanomagnet coupled to quantum spin Hall edge: An adiabatic quantum motor | The precessing magnetization of a magnetic islands coupled to a quantum spin
Hall edge pumps charge along the edge. Conversely, a bias voltage applied to
the edge makes the magnetization precess. We point out that this device
realizes an adiabatic quantum motor and discuss the efficiency of its operation
based on a sca... | 1507.06505v2 |
2017-03-28 | Temperature dependent magnetic damping of yttrium iron garnet spheres | We investigate the temperature dependent microwave absorption spectrum of an
yttrium iron garnet sphere as a function of temperature (5 K to 300 K) and
frequency (3 GHz to 43.5 GHz). At temperatures above 100 K, the magnetic
resonance linewidth increases linearly with temperature and shows a
Gilbert-like linear frequen... | 1703.09444v2 |
2017-12-10 | Magnetic field gradient driven dynamics of isolated skyrmions and antiskyrmions in frustrated magnets | The study of skyrmion/antiskyrmion motion in magnetic materials is very
important in particular for the spintronics applications. In this work, we
study the dynamics of isolated skyrmions and antiskyrmions in frustrated
magnets driven by magnetic field gradient, using the Landau-Lifshitz-Gilbert
simulations on the frus... | 1712.03550v1 |
2018-02-28 | Roles of chiral renormalization on magnetization dynamics in chiral magnets | In metallic ferromagnets, the interaction between local magnetic moments and
conduction electrons renormalizes parameters of the Landau-Lifshitz-Gilbert
equation such as the gyromagnetic ratio and the Gilbert damping, and makes them
dependent on the magnetic configurations. Although the effects of the
renormalization f... | 1803.00017v2 |
2018-12-20 | Laser Controlled Spin Dynamics of Ferromagnetic Thin Film from Femtosecond to Nanosecond Timescale | Laser induced modulation of the magnetization dynamics occurring over various
time-scales have been unified here for a Ni80Fe20 thin film excited by
amplified femtosecond laser pulses. The weak correlation between
demagnetization time and pump fluence with substantial enhancement in
remagnetization time is demonstrated... | 1812.08404v1 |
2019-03-13 | Higher-order linearly implicit full discretization of the Landau--Lifshitz--Gilbert equation | For the Landau--Lifshitz--Gilbert (LLG) equation of micromagnetics we study
linearly implicit backward difference formula (BDF) time discretizations up to
order $5$ combined with higher-order non-conforming finite element space
discretizations, which are based on the weak formulation due to Alouges but use
approximate ... | 1903.05415v2 |
2019-12-01 | Coarse-graining in micromagnetic simulations of dynamic hysteresis loops | Micromagnetic simulations based on the stochastic Landau-Lifshitz-Gilbert
equation are used to calculate dynamic magnetic hysteresis loops relevant to
magnetic hyperthermia. With the goal to effectively simulate room-temperature
loops for large iron-oxide-based systems at relatively slow sweep rates on the
order of 1 O... | 1912.00310v3 |
2020-02-17 | Self-similar shrinkers of the one-dimensional Landau-Lifshitz-Gilbert equation | The main purpose of this paper is the analytical study of self-shrinker
solutions of the one-dimensional Landau-Lifshitz-Gilbert equation (LLG), a
model describing the dynamics for the spin in ferromagnetic materials. We show
that there is a unique smooth family of backward self-similar solutions to the
LLG equation, u... | 2002.06858v2 |
2021-02-20 | Fast magnetization reversal of a magnetic nanoparticle induced by cosine chirp microwave field pulse | We investigate the magnetization reversal of single-domain magnetic
nanoparticle driven by the circularly polarized cosine chirp microwave pulse
(CCMP). The numerical findings, based on the Landau-Lifshitz-Gilbert equation,
reveal that the CCMP is by itself capable of driving fast and energy-efficient
magnetization rev... | 2102.10394v2 |
2021-07-24 | Electron-Phonon Scattering governs both Ultrafast and Precessional Magnetization Dynamics in Co-Fe Alloys | Recent investigations have advanced the understanding of how
structure-property relationships in ferromagnetic metal alloys affect the
magnetization dynamics on nanosecond time-scales. A similar understanding for
magnetization dynamics on femto- to pico-second time-scales does not yet exist.
To address this, we perform... | 2107.11699v1 |
2022-09-07 | Convergence analysis of an implicit finite difference method for the inertial Landau-Lifshitz-Gilbert equation | The Landau-Lifshitz-Gilbert (LLG) equation is a widely used model for fast
magnetization dynamics in ferromagnetic materials. Recently, the inertial LLG
equation, which contains an inertial term, has been proposed to capture the
ultra-fast magnetization dynamics at the sub-picosecond timescale.
Mathematically, this gen... | 2209.02914v2 |
2022-09-16 | Pseudo-PT symmetric Dirac equation : effect of a new mean spin angular momentum operator on Gilbert damping | The pseudo-PT symmetric Dirac equation is proposed and analyzed by using a
non-unitary Foldy-Wouthuysen transformations. A new spin operator PT symmetric
expectation value (called the mean spin operator) for an electron interacting
with a time-dependent electromagnetic field is obtained. We show that spin
magnetization... | 2209.07908v1 |
2022-11-15 | Nonlinear sub-switching regime of magnetization dynamics in photo-magnetic garnets | We analyze, both experimentally and numerically, the nonlinear regime of the
photo-induced coherent magnetization dynamics in cobalt-doped yttrium iron
garnet films. Photo-magnetic excitation with femtosecond laser pulses reveals a
strongly nonlinear response of the spin subsystem with a significant increase
of the eff... | 2211.08048v2 |
2023-08-16 | Discovery and regulation of chiral magnetic solitons: Exact solution from Landau-Lifshitz-Gilbert equation | The Landau-Lifshitz-Gilbert (LLG) equation has emerged as a fundamental and
indispensable framework within the realm of magnetism. However, solving the LLG
equation, encompassing full nonlinearity amidst intricate complexities,
presents formidable challenges. In this context, we develop a precise mapping
through geomet... | 2308.08331v1 |
1997-07-20 | Effects of gluon damping rate on the viscosity coefficient of the quark-gluon plasma at finite chemical potential | By considering the Debye screening and damping rate of gluons, the viscosity
coefficient of the quark-gluon plasma was evaluated via real-time finite
temperature QCD in the relaxation time approximation at finite temperature and
chemical potential . The results show that both the damping rate and the
chemical potential... | 9707033v1 |
2015-07-04 | Comments on turbulence theory by Qian and by Edwards and McComb | We reexamine Liouville equation based turbulence theories proposed by Qian
{[}Phys. Fluids \textbf{26}, 2098 (1983){]} and Edwards and McComb {[}J. Phys.
A: Math. Gen. \textbf{2}, 157 (1969){]}, which are compatible with Kolmogorov
spectrum. These theories obtained identical equation for spectral density
$q(k)$ and dif... | 1507.01124v1 |
2018-10-14 | Critical exponent for nonlinear damped wave equations with non-negative potential in 3D | We are studying possible interaction of damping coefficients in the
subprincipal part of the linear 3D wave equation and their impact on the
critical exponent of the corresponding nonlinear Cauchy problem with small
initial data. The main new phenomena is that certain relation between these
coefficients may cause very ... | 1810.05956v1 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.