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2020-09-22
Magnon-mediated spin currents in Tm3Fe5O12/Pt with perpendicular magnetic anisotropy
The control of pure spin currents carried by magnons in magnetic insulator (MI) garnet films with a robust perpendicular magnetic anisotropy (PMA) is of great interest to spintronic technology as they can be used to carry, transport and process information. Garnet films with PMA present labyrinth domain magnetic struct...
2009.10299v1
2020-10-17
Multiscale modelling of magnetostatic effects on magnetic nanoparticles with application to hyperthermia
We extend a renormalization group-based course-graining method for micromagnetic simulations to include properly scaled magnetostatic interactions. We apply the method in simulations of dynamic hysteresis loops at clinically relevant sweep rates and at 310 K of iron oxide nanoparticles (NPs) of the kind that have been ...
2010.08848v1
2021-02-09
Unconventional quantum vortex matter state hosts quantum oscillations in the underdoped high-temperature cuprate superconductors
A central question in the underdoped cuprates pertains to the nature of the pseudogap ground state. A conventional metallic ground state of the pseudogap region has been argued to host quantum oscillations upon destruction of the superconducting order parameter by modest magnetic fields. Here we use low applied measure...
2102.04927v2
2021-03-08
Emerging magnetic nutation
Nutation has been recognized as of great significance for spintronics; but justifying its presence has proven to be a hard problem. In this paper we show that nutation can be understood as emerging from a systematic expansion of a kernel that describes the history of the interaction of a magnetic moment with a bath of ...
2103.04787v3
2021-03-11
Long-range spin transport on the surface of topological Dirac semimetal
We theoretically propose the long-range spin transport mediated by the gapless surface states of topological Dirac semimetal (TDSM). Low-dissipation spin current is a building block of next-generation spintronics devices. While conduction electrons in metals and spin waves in ferromagnetic insulators (FMIs) are the maj...
2103.06519v1
2021-04-09
Spin diffusion length associated to out-of-plane resistivity of Pt thin films in spin pumping experiments
We present a broadband ferromagnetic resonance study of the Gilbert damping enhancement ($\Delta \alpha$) due to spin pumping in NiFe/Pt bilayers. The bilayers, which have negligible interfacial spin memory loss, are studied as a function of the Pt layer thickness ($t_{\text{Pt}}$) and temperature (100-293 K). Within t...
2104.04426v1
2021-05-05
Ni$_{80}$Fe$_{20}$ Nanotubes with Optimized Spintronic Functionalities Prepared by Atomic Layer Deposition
Permalloy Ni$_{80}$Fe$_{20}$ is one of the key magnetic materials in the field of magnonics. Its potential would be further unveiled if it could be deposited in three dimensional (3D) architectures of sizes down to the nanometer. Atomic Layer Deposition, ALD, is the technique of choice for covering arbitrary shapes wit...
2105.01969v1
2021-06-23
Spin dynamics of itinerant electrons: local magnetic moment formation and Berry phase
The state-of-the-art theoretical description of magnetic materials relies on solving effective Heisenberg spin problems or their generalizations to relativistic or multi-spin-interaction cases that explicitly assume the presence of local magnetic moments in the system. We start with a general interacting fermionic mode...
2106.12462v3
2021-11-20
Skyrmionics in correlated oxides
While chiral magnets, metal-based magnetic multilayers, or Heusler compounds have been considered as the material workhorses in the field of skyrmionics, oxides are now emerging as promising alternatives, as they host special correlations between the spin-orbital-charge-lattice degrees of freedom and/or coupled ferroic...
2111.10562v2
2021-12-01
Unconditional well-posedness and IMEX improvement of a family of predictor-corrector methods in micromagnetics
Recently, Kim & Wilkening (Convergence of a mass-lumped finite element method for the Landau-Lifshitz equation, Quart. Appl. Math., 76, 383-405, 2018) proposed two novel predictor-corrector methods for the Landau-Lifshitz-Gilbert equation (LLG) in micromagnetics, which models the dynamics of the magnetization in ferrom...
2112.00451v1
2021-12-21
Fast long-wavelength exchange spin waves in partially-compensated Ga:YIG
Spin waves in yttrium iron garnet (YIG) nano-structures attract increasing attention from the perspective of novel magnon-based data processing applications. For short wavelengths needed in small-scale devices, the group velocity is directly proportional to the spin-wave exchange stiffness constant $\lambda_\mathrm{ex}...
2112.11348v1
2022-01-27
Magnon transport and thermoelectric effects in ultrathin Tm3Fe5O12/Pt nonlocal devices
The possibility of electrically exciting and detecting magnon currents in magnetic insulators has opened exciting perspectives for transporting spin information in electronic devices. However, the role of the magnetic field and the nonlocal thermal gradients on the magnon transport remain unclear. Here, by performing n...
2201.11353v1
2022-01-31
Tuning spin-orbit torques across the phase transition in VO$_2$/NiFe heterostructure
The emergence of spin-orbit torques as a promising approach to energy-efficient magnetic switching has generated large interest in material systems with easily and fully tunable spin-orbit torques. Here, current-induced spin-orbit torques in VO$_2$/NiFe heterostructures were investigated using spin-torque ferromagnetic...
2201.12984v1
2022-02-03
Controlling spin pumping into superconducting Nb by proximity-induced spin-triplet Cooper pairs
Proximity-induced long-range spin-triplet supercurrents, important for the field of superconducting spintronics, are generated in superconducting/ferromagnetic heterostructures when interfacial magnetic inhomogeneities responsible for spin mixing and spin flip scattering are present. The multilayer stack Nb/Cr/Fe/Cr/Nb...
2202.01520v1
2022-06-17
Multiscale Modelling of the Antiferromagnet Mn2Au: From ab-initio to Micromagnetics
Antiferromagnets (AFMs) are strong candidates for the future spintronic and memory applications largely because of their inherently fast dynamics and lack of stray fields, with Mn2Au being one of the most promising. For the numerical modelling of magnetic material properties, it is common to use ab-initio methods, atom...
2206.08625v1
2022-10-29
Micromagnetic frequency-domain simulation methods for magnonic systems
We present efficient numerical methods for the simulation of small magnetization oscillations in three-dimensional micromagnetic systems. Magnetization dynamics is described by the Landau-Lifshitz-Gilbert (LLG) equation, linearized in the frequency domain around a generic equilibrium configuration, and formulated in a ...
2210.16564v3
2023-03-07
Magnon currents excited by the spin Seebeck effect in ferromagnetic EuS thin films
A magnetic insulator is an ideal platform to propagate spin information by exploiting magnon currents. However, until now, most studies have focused on Y$_3$Fe$_5$O$_{12}$ (YIG) and a few other ferri- and antiferromagnetic insulators, but not on pure ferromagnets. In this study, we demonstrate for the first time that m...
2303.03833v2
2023-04-01
A coupled magneto-structural continuum model for multiferroic $\mathrm{BiFeO}_3$
A continuum approach to study magnetoelectric multiferroic $\mathrm{BiFeO}_3$ (BFO) is proposed. Our modeling effort marries the ferroelectric (FE) phase field method and micromagnetic simulations in order to describe the entire multiferroic order parameter sector (polarization, oxygen antiphase tilts, strain, and magn...
2304.00270v1
2023-04-19
Thickness-dependent magnetic properties in Pt[CoNi]n multilayers with perpendicular magnetic anisotropy
We systematically investigated the Ni and Co thickness-dependent perpendicular magnetic anisotropy (PMA) coefficient, magnetic domain structures, and magnetization dynamics of Pt(5 nm)/[Co(t_Co nm)/Ni(t_Ni nm)]5/Pt(1 nm) multilayers by combining the four standard magnetic characterization techniques. The magnetic-relat...
2304.09366v1
2023-09-18
Coherent Tunneling and Strain Sensitivity of an All Heusler Alloy Magnetic Tunneling Junction: A First-Principles Study
Half-metallic Co-based full Heusler alloys have captured considerable attention of the researchers in the realm of spintronic applications, owing to their remarkable characteristics such as exceptionally high spin polarization at Fermi level, ultra-low Gilbert damping, and high Curie temperature. In this comprehensive ...
2309.09755v1
2023-10-27
Effect of interfacial Dzyaloshinskii-Moriya interaction in spin dynamics of an Antiferromagnet coupled Ferromagnetic double-barrier Magnetic Tunnel Junction
In this work, we have studied the spin dynamics of a synthethic Antiferromagnet (SAFM)$|$Heavy Metal (HM)$|$Ferromagnet (FM) double barrier magnetic tunnel junction (MTJ) in presence of Ruderman-Kittel-Kasuya-Yoside interaction (RKKYI), interfacial Dzyaloshinskii-Moriya interaction (iDMI), N\'eel field and Spin-Orbit C...
2310.18175v1
2023-11-14
Berry curvature induced giant intrinsic spin-orbit torque in single layer magnetic Weyl semimetal thin films
Topological quantum materials can exhibit unconventional surface states and anomalous transport properties, but their applications to spintronic devices are restricted as they require the growth of high-quality thin films with bulk-like properties. Here, we study 10--30 nm thick epitaxial ferromagnetic Co$_{\rm 2}$MnGa...
2311.08145v2
2023-12-26
All solution grown epitaxial magnonic crystal of thulium iron garnet thin film
Magnonics has shown the immense potential of compatibility with CMOS devices and the ability to be utilized in futuristic quantum computing. Therefore, the magnonic crystals, both metallic and insulating, are under extensive exploration. The presence of high spin-orbit interaction induced by the presence of rare-earth ...
2312.15973v1
2024-03-01
Spin current control of magnetism
Exploring novel strategies to manipulate the order parameter of magnetic materials by electrical means is of great importance, not only for advancing our understanding of fundamental magnetism, but also for unlocking potential practical applications. A well-established concept to date uses gate voltages to control magn...
2403.00709v1
2005-01-02
Effect of dipolar interactions on the magnetization of a cubic array of nanomagnets
We investigated the effect of intermolecular dipolar interactions on a cubic 3D ensemble of 5X5X4=100 nanomagnets, each with spin $S = 5$. We employed the Landau-Lifshitz-Gilbert equation to solve for the magnetization $M(B)$ curves for several values of the damping constant $\alpha$, the induction sweep rate, the latt...
0501006v2
2019-03-07
Uniaxial anisotropy, intrinsic and extrinsic damping in Co$_{2}$FeSi Heusler alloy thin films
Ferromagnetic resonance (FMR) technique has been used to study the magnetization relaxation processes and magnetic anisotropy in two different series of the Co2FeSi (CFS) Heusler alloy thin films, deposited on the Si(111) substrate by UHV sputtering. While the CFS films of fixed (50 nm) thickness, deposited at differen...
1903.02976v1
2023-09-19
Impact of strain on the SOT-driven dynamics of thin film Mn$_3$Sn
Mn$_3$Sn, a metallic antiferromagnet with an anti-chiral 120$^\circ$ spin structure, generates intriguing magneto-transport signatures such as a large anomalous Hall effect, spin-polarized current with novel symmetries, anomalous Nernst effect, and magneto-optic Kerr effect. When grown epitaxially as MgO(110)[001]$\par...
2309.10246v2
2008-12-31
Weak Solutions of the Stochastic Landau-Lifshitz-Gilbert Equation
The Landau-Lifshitz-Gilbert equation perturbed by a multiplicative space-dependent noise is considered for a ferromagnet filling a bounded three-dimensional domain. We show the existence of weak martingale solutions taking values in a sphere $\mathbb S^2$. The regularity of weak solutions is also discussed. Some of the...
0901.0039v1
2023-09-08
Branching points in the planar Gilbert--Steiner problem have degree 3
Gilbert--Steiner problem is a generalization of the Steiner tree problem on a specific optimal mass transportation. We show that every branching point in a solution of the planar Gilbert--Steiner problem has degree 3.
2309.04202v2
2007-02-23
Organization of the Modulopt collection of optimization problems in the Libopt environment -- Version 1.0
This note describes how the optimization problems of the Modulopt collection are organized within the Libopt environment. It is aimed at being a guide for using and enriching this collection in this environment.
0702695v1
2005-10-17
Comment on "Operator Quantum Error Correction"
The attempt to equate operator quantum error correction (quant-ph/0504189v1) with the quantum computer condition (quant-ph/0507141) in version two of quant-ph/0504189 is shown to be invalid.
0510116v1
2007-09-17
H-Decompositions
We show that for all graphs H of size n, the complete graph $K_{2n+1}$ has an $H$-decomposition.
0709.2525v5
2008-10-06
Unsolvability of the isomorphism problem for [free abelian]-by-free groups
The isomorphism problem for [free abelian]-by-free groups is unsolvable.
0810.0935v2
2011-11-27
Comment on "Capturing correlations in chaotic diffusion by approximation methods"
This is a comment on [G. Knight and R. Klages, Phys. Rev. E 84, 041135 (2011); also available at arXiv:1107.5293v2 [math-ph]].
1111.6271v1
2014-01-11
Hashimoto transform for stochastic Landau-Lifshitz-Gilbert equation
We show that Hashimoto transformation is applicable to the one dimensional stochastic Landau-Lifshitz-Gilbert (LLG) equation and transforms it to the stochastic generalized heat equation with nonlocal (in space) interaction.
1401.2520v1
2017-01-04
Non-linear Cyclic Codes that Attain the Gilbert-Varshamov Bound
We prove that there exist non-linear binary cyclic codes that attain the Gilbert-Varshamov bound.
1701.01043v1
2019-01-28
Conformal deformations preserving the Finslerian $R$-Einstein criterion
Given a Finslerian metric $F$ on a $C^4$-manifold, conformal deformations of $F$ preserving the $R$-Einstein criterion are presented. In particular, locally conformal invariance between two Finslerian $R$-Einstein metrics is characterized.
1902.00069v1
2022-04-07
How to design a network architecture using availability
The best way to design a network is to take into account Availability values and Capacity Planning. You already saw Availability expressed with numbers such as 99.99%. The purpose of this document is to introduce the way to compute Availability values using Reliability Block Diagrams.
2204.03311v1
2010-02-22
Transport and magnetization dynamics in a superconductor/single-molecule magnet/superconductor junction
We study dc-transport and magnetization dynamics in a junction of arbitrary transparency consisting of two spin-singlet superconducting leads connected via a single classical spin precessing at the frequency $\Omega$. The presence of the spin in the junction provides different transmission amplitudes for spin-up and sp...
1002.3929v4
2013-06-18
Baryons do trace dark matter 380,000 years after the big bang: Search for compensated isocurvature perturbations with WMAP 9-year data
Primordial isocurvature fluctuations between photons and either neutrinos or non-relativistic species such as baryons or dark matter are known to be sub-dominant to adiabatic fluctuations. Perturbations in the relative densities of baryons and dark matter (known as compensated isocurvature perturbations, or CIPs), howe...
1306.4319v1
2015-05-29
Microscopic Theory for Coupled Atomistic Magnetization and Lattice Dynamics
A coupled atomistic spin and lattice dynamics approach is developed which merges the dynamics of these two degrees of freedom into a single set of coupled equations of motion. The underlying microscopic model comprises local exchange interactions between the electron spin and magnetic moment and the local couplings bet...
1505.08005v3
2016-04-28
Dynamics of skyrmionic states in confined helimagnetic nanostructures
In confined helimagnetic nanostructures, skyrmionic states in the form of incomplete and isolated skyrmion states can emerge as the ground state in absence of both external magnetic field and magnetocrystalline anisotropy. In this work, we study the dynamic properties (resonance frequencies and corresponding eigenmodes...
1604.08347v2
2017-04-13
Low energy magnon dynamics and magneto-optics of the skyrmionic Mott insulator Cu$_2$OSeO$_3$
In this work, we present a comprehensive study of the low energy optical magnetic response of the skyrmionic Mott insulator Cu$_2$OSeO$_3$ via high resolution time-domain THz spectroscopy. In zero field, a new magnetic excitation not predicted by spin-wave theory with frequency $f$ = 2.03 THz is observed and shown, wit...
1704.04228v1
2017-08-25
Role of dimensional crossover on spin-orbit torque efficiency in magnetic insulator thin films
Magnetic insulators (MIs) attract tremendous interest for spintronic applications due to low Gilbert damping and absence of Ohmic loss. Magnetic order of MIs can be manipulated and even switched by spin-orbit torques (SOTs) generated through spin Hall effect and Rashba-Edelstein effect in heavy metal/MI bilayers. SOTs ...
1708.07584v2
2018-07-04
Phase Boundary Exchange Coupling in the Mixed Magnetic Phase Regime of a Pd-doped FeRh Epilayer
Spin-wave resonance measurements were performed in the mixed magnetic phase regime of a Pd-doped FeRh epilayer that appears as the first-order ferromagnetic-antiferromagnetic phase transition takes place. It is seen that the measured value of the exchange stiffness is suppressed throughout the measurement range when co...
1807.01615v6
2018-07-26
EPIC 246851721 b: A Tropical Jupiter Transiting a Rapidly Rotating Star in a Well-Aligned Orbit
We report the discovery of EPIC 246851721 b, a "tropical" Jupiter in a 6.18-day orbit around the bright ($V=11.439$) star EPIC 246851721 (TYC 1283-739-1). We present a detailed analysis of the system using $K2$ and ground-based photometry, radial velocities, Doppler tomography and adaptive optics imaging. From our glob...
1807.10298v2
2018-09-10
Magnetic properties and field-driven dynamics of chiral domain walls in epitaxial Pt/Co/Au$_x$Pt$_{1-x}$ trilayers
Chiral domain walls in ultrathin perpendicularly magnetised layers have a N\'{e}el structure stabilised by a Dzyaloshinskii-Moriya interaction (DMI) that is generated at the interface between the ferromagnet and a heavy metal. Different heavy metals are required above and below a ferromagnetic film in order to generate...
1809.03217v2
2019-09-06
Macrospin analysis of RF excitations within fully perpendicular magnetic tunnel junctions with second order easy-axis magnetic anisotropy contribution
The conditions of field and voltage for inducing steady state excitations in fully perpendicular magnetic tunnel junctions (pMTJs), adapted for memory applications, were numerically investigated by the resolution of the Landau-Lifshitz-Gilbert equation in the macrospin approach. Both damping-like and the field-like spi...
1909.02926v1
2021-04-21
Atomic Layer Deposition of Yttrium Iron Garnet Thin Films for 3D Magnetic Structures
A wide variety of new phenomena such as novel magnetization configurations have been predicted to occur in three dimensional magnetic nanostructures. However, the fabrication of such structures is often challenging due to the specific shapes required, such as magnetic tubes and spirals. Furthermore, the materials curre...
2104.10293v2
2022-11-03
Skyrmion Jellyfish in Driven Chiral Magnets
Chiral magnets can host topological particles known as skyrmions, which carry an exactly quantised topological charge $Q=-1$. In the presence of an oscillating magnetic field ${\bf B}_1(t)$, a single skyrmion embedded in a ferromagnetic background will start to move with constant velocity ${\bf v}_{\text{trans}}$. The ...
2211.01714v5
2023-04-05
Threshold current of field-free perpendicular magnetization switching using anomalous spin-orbit torque
Spin-orbit torque (SOT) is a candidate technique in next generation magnetic random-access memory (MRAM). Recently, experiments show that some material with low-symmetric crystalline or magnetic structures can generate anomalous SOT that has an out-of-plane component, which is crucial in switching perpendicular magneti...
2304.02248v2
2023-08-07
$\textit{In situ}$ electric-field control of ferromagnetic resonance in the low-loss organic-based ferrimagnet V[TCNE]$_{x\sim 2}$
We demonstrate indirect electric-field control of ferromagnetic resonance (FMR) in devices that integrate the low-loss, molecule-based, room-temperature ferrimagnet vanadium tetracyanoethylene (V[TCNE]$_{x \sim 2}$) mechanically coupled to PMN-PT piezoelectric transducers. Upon straining the V[TCNE]$_x$ films, the FMR ...
2308.03353v1
2023-08-18
Large thermo-spin effects in Heusler alloy based spin-gapless semiconductor thin films
Recently, Heusler alloys-based spin gapless semiconductors (SGSs) with high Curie temperature (TC) and sizeable spin polarization have emerged as potential candidates for tunable spintronic applications. We report comprehensive investigation of the temperature dependent ANE and intrinsic longitudinal spin Seebeck effec...
2308.09843v1
2017-07-28
Measurements of the Temperature and E-Mode Polarization of the CMB from 500 Square Degrees of SPTpol Data
We present measurements of the $E$-mode polarization angular auto-power spectrum ($EE$) and temperature-$E$-mode cross-power spectrum ($TE$) of the cosmic microwave background (CMB) using 150 GHz data from three seasons of SPTpol observations. We report the power spectra over the spherical harmonic multipole range $50 ...
1707.09353v3
2021-02-09
Binet's factorial series and extensions to Laplace transforms
We investigate a generalization of Binet's factorial series in the parameter $\alpha$ \[ \mu\left( z\right) =\sum_{m=1}^{\infty}\frac{b_{m}\left( \alpha\right) }{\prod_{k=0}^{m-1}(z+\alpha+k)}% \] due to Gilbert, for the Binet function \[ \mu\left( z\right) =\log\Gamma\left( z\right) -\left( z-\frac{1} {2}\right) \log ...
2102.04891v7
2000-05-29
Entropy Production in a Persistent Random Walk
We consider a one-dimensional persisent random walk viewed as a deterministic process with a form of time reversal symmetry. Particle reservoirs placed at both ends of the system induce a density current which drives the system out of equilibrium. The phase space distribution is singular in the stationary state and has...
0005063v1
2012-12-13
A convergent finite element approximation for the quasi-static Maxwell--Landau--Lifshitz--Gilbert equations
We propose a $\theta$-linear scheme for the numerical solution of the quasi-static Maxwell-Landau-Lifshitz-Gilbert (MLLG) equations. Despite the strong nonlinearity of the Landau-Lifshitz-Gilbert equation, the proposed method results in a linear system at each time step. We prove that as the time and space steps tend t...
1212.3369v1
2013-09-28
Global Well-Posedness of the Landau-Lifshitz-Gilbert equation for initial data in Morrey space
We establish the global well-posedness of the Landau-Lifshitz-Gilbert equation in $\mathbb R^n$ for any initial data ${\bf m}_0\in H^1_*(\mathbb R^n,\mathbb S^2)$ whose gradient belongs to the Morrey space $M^{2,2}(\mathbb R^n)$ with small norm $\displaystyle\|\nabla {\bf m}_0\|_{M^{2,2}(\mathbb R^n)}$. The method is b...
1309.7426v1
2016-10-26
Iterated Gilbert Mosaics and Poisson Tropical Plane Curves
We propose an iterated version of the Gilbert model, which results in a sequence of random mosaics of the plane. We prove that under appropriate scaling, this sequence of mosaics converges to that obtained by a classical Poisson line process with explicit cylindrical measure. Our model arises from considerations on tro...
1610.08533v1
2017-05-29
Strong solvability of regularized stochastic Landau-Lifshitz-Gilbert equation
We examine a stochastic Landau-Lifshitz-Gilbert equation based on an exchange energy functional containing second-order derivatives of the unknown field. Such regularizations are featured in advanced micromagnetic models recently introduced in connection with nanoscale topological solitons. We show that, in contrast to...
1705.10184v1
2021-04-03
Improving the Gilbert-Varshamov Bound by Graph Spectral Method
We improve Gilbert-Varshamov bound by graph spectral method. Gilbert graph $G_{q,n,d}$ is a graph with all vectors in $\mathbb{F}_q^n$ as vertices where two vertices are adjacent if their Hamming distance is less than $d$. In this paper, we calculate the eigenvalues and eigenvectors of $G_{q,n,d}$ using the properties ...
2104.01403v3
2006-02-20
Fluctuation theorem applied to the Nosé-Hoover thermostated Lorentz gas
We present numerical evidence supporting the validity of the Gallavotti-Cohen Fluctuation Theorem applied to the driven Lorentz gas with Nos\'e-Hoover thermostating. It is moreover argued that the asymptotic form of the fluctuation formula is independent of the amplitude of the driving force, in the limit where it is s...
0602458v1
1997-12-28
Model-independent $\tan β$ bounds in the MSSM
We demonstrate, through the study of the one-loop effective potential in the MSSM, the existence of fully model-independent lower and upper theoretical bounds on $\tan \beta$. We give their general analytic form and illustrate some of their implications.
9712529v1
2006-12-26
Very Light Gravitino Dark Matter
We address the question of dark matter in the context of gauge mediated supersymmetry breaking models. In contrast with mSUGRA scenarios, the messenger of the susy breaking to the visible sector can play an important role allowing a relic gravitino in the $\sim {keV}$ to $10 {MeV}$ mass range to account for the cold da...
0612331v1
2004-09-15
Characterizing rigid simplicial actions on trees
We extend Forester's rigidity theorem so as to give a complete characterization of rigid group actions on trees (an action is rigid if it is the only reduced action in its deformation space, in particular it is invariant under automorphisms preserving the set of elliptic subgroups).
0409245v1
2005-12-14
Efficient Construction of Photonic Quantum Computational Clusters
We demonstrate a method of creating photonic two-dimensional cluster states that is considerably more efficient than previously proposed approaches. Our method uses only local unitaries and type-I fusion operations. The increased efficiency of our method compared to previously proposed constructions is obtained by iden...
0512110v1
2007-10-26
The dark matter as a light gravitino
We address the question of gravitino dark matter in the context of gauge mediated supersymmetry breaking models. A special emphasis is put on the role played by the MSSM singlet messenger in the case of SO(10) grand unification.
0710.5121v1
2008-03-05
Innovative Weak Formulation for The Landau-Lifshitz-Gilbert Equations
A non-conventional finite element formalism is proposed to solve the dynamic Landau-Lifshitz-Gilbert micromagnetic equations. Two bidimensional test problems are treated to estimate the validity and the accuracy of this finite element approach
0803.0599v1
2008-10-27
The profile of bubbling solutions of a class of fourth order geometric equations on 4-manifolds
We study a class of fourth order geometric equations defined on a 4-dimensional compact Riemannian manifold which includes the Q-curvature equation. We obtain sharp estimates on the difference near the blow-up points between a bubbling sequence of solutions and the standard bubble.
0810.4879v1
2009-03-02
Asymptotic Improvement of the Binary Gilbert-Varshamov Bound on the Code Rate
We compute the code parameters for binary linear codes obtained by greedy constructing the parity check matrix. Then we show that these codes improve the Gilbert-Varshamov (GV) bound on the code size and rate. This result counter proves the conjecture on the asymptotical exactness of the binary GV bound.
0903.0302v2
2009-11-16
The Independent Chip Model and Risk Aversion
We consider the Independent Chip Model (ICM) for expected value in poker tournaments. Our first result is that participating in a fair bet with one other player will always lower one's expected value under this model. Our second result is that the expected value for players not participating in a fair bet between two p...
0911.3100v1
2011-03-29
Statistical properties of $r$-adic processes and their connections to families of popular fractal curves
Results concerning the statists of $r$-adic processes and their fractal properties are reviewed. The connection between singular eigenstates of the statistical evolution of such processes and popular fractal curves is emphasized.
1103.5683v1
2011-05-09
Global Solvability of the Cauchy Problem for the Landau-Lifshitz-Gilbert Equation in Higher Dimensions
We prove existence, uniqueness and asymptotics of global smooth solutions for the Landau-Lifshitz-Gilbert equation in dimension $n \ge 3$, valid under a smallness condition of initial gradients in the $L^n$ norm. The argument is based on the method of moving frames that produces a covariant complex Ginzburg-Landau equa...
1105.1597v1
2012-03-28
Fibonacci numbers in phyllotaxis : a simple model
A simple model is presented which explains the occurrence of high order Fibonacci number parastichies in asteracae flowers by two distinct steps. First low order parastichies result from the fact that a new floret, at its appearance is repelled by two former ones, then, in order to accommodate for the increase of the r...
1203.6257v1
2014-02-19
Ordered groupoids and the holomorph of an inverse semigroup
We present a construction for the holomorph of an inverse semigroup, derived from the cartesian closed structure of the category of ordered groupoids. We compare the holomorph with the monoid of mappings that preserve the ternary heap operation on an inverse semigroup: for groups these two constructions coincide. We pr...
1402.4592v1
2014-11-01
Functorial Zeta Integrals
The functional equation for nonarchimedean Rankin-Selberg local Euler factors was proved by Jacquet, Piatetski-Shapiro, and Shalika in 1983. In this expository note we translate the original proof into the purely functorial language of parabolic induction-restriction of Bernstein-Zelevinsky. This new language gives a c...
1411.0148v1
2016-02-17
Dispersion and Scaling Law of Dynamic Hysteresis Based on the Landau-Lifshitz-Gilbert Model
Hysteresis dispersion under a varying external field Hex is investigated through numerical simulations based on the Landau-Lifshitz-Gilbert (LLG) equation, indicating the energy dissipation can be determined by W({\eta}) = A (f, H0). A linear relation between area of hysteresis and magnitude of external field is discov...
1602.05375v1
2016-06-06
Proof of tightness of Varshamov - Gilbert bound for binary codes
We prove tightness of right logarithmic asymptotic of Varshamov- Gilbert bound for linear binary codes We find general asymptotic coding bound for linear codes
1606.01592v5
2017-02-21
Cohomology and extensions of ordered groupoids
We adapt and generalise results of Loganathan on the cohomology of inverse semigroups to the cohomology of ordered groupoids. We then derive a five-term exact sequence in cohomology from an extension of ordered groupoids, and show that this sequence leads to a classification of extensions by a second cohomology group. ...
1702.06333v1
2017-05-11
Two Gilbert-Varshamov Type Existential Bounds for Asymmetric Quantum Error-Correcting Codes
In this note we report two versions of Gilbert-Varshamov type existential bounds for asymmetric quantum error-correcting codes.
1705.04087v2
2017-09-21
Self-Dual Codes better than the Gilbert--Varshamov bound
We show that every self-orthogonal code over $\mathbb F_q$ of length $n$ can be extended to a self-dual code, if there exists self-dual codes of length $n$. Using a family of Galois towers of algebraic function fields we show that over any nonprime field $\mathbb F_q$, with $q\geq 64$, except possibly $q=125$, there ar...
1709.07221v1
2018-10-12
A convex approach to the Gilbert-Steiner problem
We describe a convex relaxation for the Gilbert-Steiner problem both in $R^d$ and on manifolds, extending the framework proposed in [9], and we discuss its sharpness by means of calibration type arguments. The minimization of the resulting problem is then tackled numerically and we present results for an extensive set ...
1810.05417v1
2018-11-09
Finslerian metrics locally conformally $R$-Einstein
Let $R$ be the $hh$-curvature associated with the Chern connection or the Cartan connection. Adopting the pulled-back tangent bundle approach to the Finslerian Geometry, an intrinsic characterization of $R$-Einstein metrics is given. Finslerian metrics which are locally conformally $R$-Einstein are classified.
1811.04077v3
2019-02-05
Harmonic maps with prescribed singularities and applications in general relativity
This paper presents a general existence and uniqueness result for harmonic maps with prescribed singularities into non-positively curved targets, and surveys a number of applications to general relativity. It is based on a talk delivered by the author at The 11th Mathematical Society of Japan Seasonal Institute, The Ro...
1902.01576v2
2020-03-13
3D Stochastic Landau-Lifshitz-Gilbert Equations coupled with Maxwell's Equations with full energy
We consider 3D stochastic Landau-Lifshitz-Gilbert equations coupled with the Maxwell equations with the full energy. We have proved the existence and some further regularities of the weak solution.
2003.06091v4
2021-12-09
Induced Semi-Riemannian structures on null submanifolds
In this paper, we induce a semi-Riemannian metric on the $r$-null submanifold. We establish the links between the null geometry and basics invariants of the associated semi-Riemannian geometry on $r$-null submanifold and semi-Riemannian constructed from a semi-Riemannian ambient.
2112.07348v1
2022-04-12
How to design a network architecture using capacity planning
Building a network architecture must answer to organization needs, but also to two major elements which are the need for dependability and performance. By performance, we must understand the ability to meet an immediate need and the ability to scale without reducing the performance of the whole as new elements are adde...
2204.05916v2
2022-07-31
Moduli of Representations of Skewed-Gentle Algebras
We prove irreducible components of moduli spaces of semistable representations of skewed-gentle algebras, and more generally, clannish algebras, are isomorphic to products of projective spaces. This is achieved by showing irreducible components of varieties of representations of clannish algebras can be viewed as irred...
2208.00336v1
2022-08-01
iOCR: Informed Optical Character Recognition for Election Ballot Tallies
The purpose of this study is to explore the performance of Informed OCR or iOCR. iOCR was developed with a spell correction algorithm to fix errors introduced by conventional OCR for vote tabulation. The results found that the iOCR system outperforms conventional OCR techniques.
2208.00865v1
2023-03-13
Adaptive mesh refinement for the Landau-Lifshitz-Gilbert equation
We propose a new adaptive algorithm for the approximation of the Landau-Lifshitz-Gilbert equation via a higher-order tangent plane scheme. We show that the adaptive approximation satisfies an energy inequality and demonstrate numerically, that the adaptive algorithm outperforms uniform approaches.
2303.07463v1
2023-05-08
Evaluation of the Gilbert-Varshamov Bound using Multivariate Analytic Combinatorics
Analytic combinatorics in several variables refers to a suite of tools that provide sharp asymptotic estimates for certain combinatorial quantities. In this paper, we apply these tools to determine the Gilbert-Varshamov (GV) bound for the sticky insertion and the constrained-synthesis channel.
2305.04439v1
2023-12-11
Matrix Formulae and Skein Relations for Quasi-cluster Algebras
In this paper, we give matrix formulae for non-orientable surfaces that provide the Laurent expansion for quasi-cluster variables, generalizing the orientable surface matrix formulae by Musiker-Williams. We additionally use our matrix formulas to prove the skein relations for the elements in the quasi-cluster algebra a...
2312.06148v1
2009-08-12
Linear Fractionally Damped Oscillator
In this paper the linearly damped oscillator equation is considered with the damping term generalized to a Caputo fractional derivative. The order of the derivative being considered is 0 less than or equal to nu which is less than or equal to 1 . At the lower end, nu = 0, the equation represents an un-damped oscillator...
0908.1683v1
2004-05-06
On a theorem of Kac and Gilbert
We prove a general operator theoretic result that asserts that many multiplicity two selfadjoint operators have simple singular spectrum.
0405110v1
2011-01-05
Beating the Gilbert-Varshamov Bound for Online Channels
In the online channel coding model, a sender wishes to communicate a message to a receiver by transmitting a codeword x =(x_1,...,x_n) in {0,1}^n bit by bit via a channel limited to at most pn corruptions. The channel is online in the sense that at the ith step the channel decides whether to flip the ith bit or not and...
1101.1045v1
2014-11-25
From heavy-tailed Boolean models to scale-free Gilbert graphs
Define the scale-free Gilbert graph based on a Boolean model with heavy-tailed radius distribution on the $d$-dimensional torus by connecting two centers of balls by an edge if at least one of the balls contains the center of the other. We investigate two asymptotic properties of this graph as the size of the torus ten...
1411.6824v1
2016-03-16
Recent Results from SPLASH: Chemical Abundances and Kinematics of Andromeda's Stellar Halo
Large scale surveys of Andromeda's resolved stellar populations have revolutionized our view of this galaxy over the past decade. The combination of large-scale, contiguous photometric surveys and pointed spectroscopic surveys has been particularly powerful for discovering substructure and disentangling the structural ...
1603.05160v1
2017-05-09
Gilbert's disc model with geostatistical marking
We study a variant of Gilbert's disc model, in which discs are positioned at the points of a Poisson process in $\mathbb{R}^2$ with radii determined by an underlying stationary and ergodic random field $\varphi:\mathbb{R}^2\to[0,\infty)$, independent of the Poisson process. When the random field is independent of the p...
1705.03337v2
2019-01-30
Is the mailing Gilbert-Steiner problem convex?
A convexification of the mailing version of the finite Gilbert problem for optimal networks is introduced. It is ia convex functional on the set of probability measures subject to the Wasserstein $p-$ metric. The minimizer of this convex functional is a measure supported in a graph. If this graph is a tree (i.e contain...
1901.10924v4
2019-11-06
Phase transitions for chase-escape models on Gilbert graphs
We present results on phase transitions of local and global survival in a two-species model on Gilbert graphs. At initial time there is an infection at the origin that propagates on the Gilbert graph according to a continuous-time nearest-neighbor interacting particle system. The Gilbert graph consists of susceptible n...
1911.02622v2