publicationDate
stringlengths
1
2.79k
title
stringlengths
1
36.5k
abstract
stringlengths
1
37.3k
id
stringlengths
9
47
2014-06-12
Gyratonic pp-waves and their impulsive limit
We investigate a class of gravitational pp-waves which represent the exterior vacuum field of spinning particles moving with the speed of light. Such exact spacetimes are described by the original Brinkmann form of the pp-wave metric including the often neglected off-diagonal terms. We put emphasis on a clear physical ...
1406.3227v2
2004-05-27
Excitation of magnetostatic spin waves in ferromagnetic films
The torque equation of nonlinear spin dynamics is considered in the magnetostatic approximation. In this framework, exact expressions for propagator of linear magnetostatic waves in ferromagnetic film between two antennas and corresponding mutual impedance of the antennas are derived, under conditions of uniform but ar...
0405640v1
2023-07-05
Lifshitz model in the presence of spin-orbit coupling
Wave function of a localized state created by a short-range impurity in two dimensions falls off with distance, r, from the impurity as r^{-1/2}exp(-r/a), where "a" is the localization radius. With randomly positioned identical impurities with low concentration, n<<a^{-2}, the level smears into a band due to the overla...
2307.01971v1
2023-10-26
Spontaneously sliding multipole spin density waves in cold atoms
We report on the observation of spontaneously drifting coupled spin and quadrupolar density waves in the ground state of laser driven Rubidium atoms. These laser-cooled atomic ensembles exhibit spontaneous magnetism via light mediated interactions when submitted to optical feedback by a retro-reflecting mirror. Drift d...
2310.17305v2
2024-01-16
Wave packet treatment of neutrino flavour and spin oscillations in galactic and extragalactic magnetic fields
We consider neutrino flavour and spin oscillations in a magnetic field using formalism of wave packets. Decoherence effects due to neutrino wave packets separation are studied. The considered effects are especially important for describing astrophysical neutrino oscillations, since they propagate on kiloparsec scale an...
2401.08724v2
2013-03-01
Generation of Electrostatic Waves via Parametric Instability and Heating of Solar Corona
In the upper layers of the solar atmosphere the temperature increases sharply. We studied possibility of the transfer of neutrals motion energy into the electrostatic waves.Electrostatic waves could damp in the upper layers of the solar atmosphere and their energy could be transformed into the thermal energy of the sol...
1303.0151v1
2018-05-31
Bending Waves in the Milky Way's disc from halo substructure
We use $N$-body simulations to investigate the excitation of bending waves in a Milky Way-like disc-bulge-halo system. The dark matter halo consists of a smooth component and a population of subhaloes while the disc is composed of thin and thick components. Also considered is a control simulation where all of the halo ...
1805.12449v2
2020-11-20
Whistler Waves in the foot of Quasi-Perpendicular Super-Critical Shocks
Whistler waves are thought to play an essential role in the dynamics of collisionless shocks. We use the magnetospheric multiscale (MMS) spacecraft to study whistler waves around the lower hybrid frequency, upstream of 11 quasi-perpendicular super-critical shocks. We apply the 4-spacecraft timing method to unambiguousl...
2011.10593v4
2021-04-06
Modeling interactions of narrowband large amplitude whistler-mode waves with electrons in the solar wind inside ~.3 AU and at 1 AU using a particle tracing code
The discovery of large-amplitude narrowband whistler-mode waves at frequencies of tenths of the electron cyclotron frequency in large numbers both inside ~.3 AU and at ~1 AU provides an answer to longstanding questions about scattering and energization of solar wind electrons. The waves can have rapid nonlinear interac...
2104.02824v1
2022-11-10
Intense whistler-mode waves at foreshock transients: characteristics and regimes of wave-particle resonant interaction
Thermalization and heating of plasma flows at shocks result in unstable charged-particle distributions which generate a wide range of electromagnetic waves. These waves, in turn, can further accelerate and scatter energetic particles. Thus, the properties of the waves and their implication for wave-particle interaction...
2211.05398v1
2023-03-17
Nonlinear dynamics of small-scale Alfvén waves
We study the nonlinear evolution of very oblique small-scale Alfv\'en waves with $k_\perp d_i\gtrsim 1$. At these scales, the waves become significantly compressive, unlike in MHD, due to the Hall term in the equations. We demonstrate that when frequencies are small compared to the ion gyrofrequency and amplitudes smal...
2303.10192v1
2004-05-28
Hyperfine interaction in a quantum dot: Non-Markovian electron spin dynamics
We have performed a systematic calculation for the non-Markovian dynamics of a localized electron spin interacting with an environment of nuclear spins via the Fermi contact hyperfine interaction. This work applies to an electron in the s -type orbital ground state of a quantum dot or bound to a donor impurity, and is ...
0405676v2
1995-08-16
Stochastic Particle Acceleration near Accreting Black Holes
We consider the stochastic acceleration of particles which results from resonant interactions with plasma waves in black hole magnetospheres. We calculate acceleration rates and escape time scales for protons and electrons resonating with Alfv\'en waves, and for electrons resonating with whistlers. Assuming either a Ko...
9508069v1
2005-11-01
Disk heating by more than one spiral density wave
We consider a differentially rotating, 2D stellar disk perturbed by two steady state spiral density waves moving at different patterns speeds. Our investigation is based on direct numerical integration of initially circular test-particle orbits. We examine a range of spiral strengths and spiral speeds and show that sta...
0511037v1
2006-04-09
Three-dimensional strong localization of matter waves by scattering from atoms in a lattice with a confinement-induced resonance
The possibility of using ultracold atoms to observe strong localization of matter waves is now the subject of a great interest, as undesirable decoherence and interactions can be made negligible in these systems. It was proposed that a static disordered potential can be realized by trapping atoms of a given species in ...
0604232v2
2005-10-28
Radial disk heating by more than one spiral density wave
We consider a differentially rotating, 2D stellar disk perturbed by two steady state spiral density waves moving at different patterns speeds. Our investigation is based on direct numerical integration of initially circular test-particle orbits. We examine a range of spiral strengths and spiral speeds and show that sta...
0510074v1
2009-09-27
Space-time symmetry violation of the fields in quasi-2D ferrite particles with magnetic-dipolar-mode oscillations
In magnetic systems with reduced dimensionality, the effects of dipolar interactions allow the existence of long-range ordered phases. Long-range magnetic-dipolar interactions are at the heart of the explanation of many peculiar phenomena observed in nuclear magnetic resonance, ferromagnetic resonance, and Bose-Einstei...
0909.4920v1
2015-06-30
Resonant Absorption of Transverse Oscillations and Associated Heating in a Solar Prominence. I- Observational aspects
Transverse magnetohydrodynamic (MHD) waves have been shown to be ubiquitous in the solar atmosphere and can in principle carry sufficient energy to generate and maintain the Sun's million-degree outer atmosphere or corona. However, direct evidence of the dissipation process of these waves and subsequent heating has not...
1506.08965v1
2017-11-01
Realization of a Contactless Acoustic Levitation Motor via Doublet Mode Control and Autoresonance
This paper demonstrates analytically and experimentally an acoustic levitation motor which has the ability to levitate and rotate an object in the air without mechanical contact. To realize such a device two core methods are applied simultaneously; (i) resonance tracking with an Autoresonance feedback loop, (ii) genera...
1711.00380v1
2018-03-29
The linear theory of tidally excited spiral density waves: application to CV and circumplanetary disks
We revisit linear tidal excitation of spiral density waves in the disks of cataclysmic variables (CVs), focusing on scalings with orbital Mach number in order to bridge the gap between numerical simulations and real systems. If an inner Lindblad resonance (ILR) lies within the disk, ingoing waves are robustly excited, ...
1803.10921v1
2019-11-01
Free and forced wave propagation in beam lattice metamaterials with viscoelastic resonators
Beam lattice materials are characterized by a periodic microstructure realizing a geometrically regular pattern of elementary cells. In these microstructured materials, the dispersion properties governing the free dynamic propagation of elastic waves can be studied by formulating parametric lagrangian models and applyi...
1911.00455v1
2018-08-14
Wave propagation in infinite nonlinear acoustic metamaterial beam by considering the third harmonic generation
Nonlinear acoustic metamaterial (NAM) initiates new fields for controlling elastic waves. In this work, the flexural wave propagation in the half-infinite NAM beam consisting of periodic Duffing resonators is reported by considering the third harmonic generation (THG). Different analytical methods are proposed to descr...
1808.04682v2
2017-06-15
Resonant drag instability of grains streaming in fluids
We show that grains streaming through a fluid are generically unstable if their velocity, projected along some direction, matches the phase velocity of a fluid wave (linear oscillation). This can occur whenever grains stream faster than any fluid wave. The wave itself can be quite general--sound waves, magnetosonic wav...
1706.05020v5
2017-10-25
Electromagnetic waves propagating in the string axiverse
It is widely believed that axions are ubiquitous in string theory and could be the dark matter. The peculiar features of the axion dark matter are coherent oscillations and a coupling to the electromagnetic field through the Chern-Simons term. In this paper, we study consequences of these two features of the axion with...
1710.09198v2
2017-03-21
Two-body Wave Functions, Compositeness, And The Internal Structure Of Dynamically Generated Resonances
Recently, the compositeness, defined as the norm of a two-body wave function for bound and resonance states, has been investigated to discuss the internal structure of hadrons in terms of hadronic molecular components. From the studies of the compositeness, it has been clarified that the two-body wave function of a bou...
1703.07176v1
2019-04-10
The role of resonance and bandgaps in high $k_\textrm{eff}^2$ transducers
Bandgaps formed in a piezoelectric transducer with large coupling, $k_\textrm{eff}^2$, qualitatively modify its electrical response. This regime in which electrical loading strongly couples forward and backward waves occurs in thin-film lithium niobate which has recently become available and amenable to nanopatterning....
1904.04981v1
2019-12-22
Scattering from compact objects: Regge poles and the complex angular momentum method
We calculate the Regge poles of the scattering matrix for a gravitating compact body, for scalar fields and for gravitational waves in the axial sector. For a neutron-starlike body, the spectrum exhibits two distinct branches of poles, labeled surface waves and broad resonances; for ultracompact objects, the spectrum a...
1912.11348v2
2022-01-09
Acoustics of a partially partitioned narrow slit connected to a half-plane: case study for exponential quasi-bound states in the continuum and their resonant excitation
Localised wave oscillations in an open system that do not decay or grow in time, despite their frequency lying within a continuous spectrum of radiation modes carrying energy to or from infinity, are known as bound states in the continuum (BIC). Small perturbations from the typically delicate conditions for BIC almost ...
2201.03554v1
2023-07-14
A resonant Lyapunov centre theorem with an application to doubly periodic travelling hydroelastic waves
We present a Lyapunov centre theorem for an antisymplectically reversible Hamiltonian system exhibiting a nondegenerate $1:1$ or $1:-1$ semisimple resonance as a detuning parameter is varied. The system can be finite- or infinite dimensional (and quasilinear) and have a non-constant symplectic structure. We allow the o...
2307.07194v1
2024-02-27
A computational method for angle-resolved photoemission spectra from repeated-slab band structure calculations
A versatile method for angle-resolved photoemission spectra (ARPES) calculations is reported within the one-step model of photoemission. The initial states are obtained from a repeated-slab calculation using the projector-augmented wave (PAW) method. ARPES final states are constructed by matching the repeated-slab eige...
2402.17199v1
2004-12-29
An analytic study of the gravitational wave pulsar signal with spin down effects
In this work, we present the analytic treatment of the Fourier Transform (FT) of the Gravitational Wave (GW) signal from a pulsar including spin down corrections in a parametrized model discussed by Brady et. al. The formalism lends itself to a development of the FT in terms of well known special functions and integral...
0412646v1
1992-11-24
Possible Quantum Spin Liquid States on the Triangular and Kagome Lattices
The frustrated spin-one-half Heisenberg model on triangualr and Kagome Lattices is mapped onto a single specis of fermion carrying statistical flux. The corresponding Chern-Simons gauge theory is analyzed at the Gaussian level and found to be massive. This provides a new motivation for the spin-liquid Kalmeyer-Laughlin...
9211017v1
1993-10-11
Half-Integral Spin-Singlet Quantum Hall Effect
We provide numerical evidence that the ground state of a short range interaction model at $\nu=1/2$ is incompressible and spin-singlet for a wide range of repulsive interactions. Furthermore it is accurately described by a trial wave function studied earlier. For the Coulomb interaction we find that this wave function ...
9310020v1
1994-04-18
Intensity correlations in electronic wave propagation in a disordered medium: the influence of spin-orbit scattering
We obtain explicit expressions for the correlation functions of transmission and reflection coefficients of coherent electronic waves propagating through a disordered quasi-one-dimensional medium with purely elastic diffusive scattering in the presence of spin-orbit interactions. We find in the metallic regime both lar...
9404054v1
1997-09-26
Scaling relation of spin wave lifetime in double-exchange systems
Spin excitation spectrum of CMR manganites are studied from both theoretical and experimental sides. Scaling relations for the spin wave lifetime in the electronic model with double-exchange interaction is observed, which is consistent with results for neutron inelastic scattering experiments for (La,Y)$_{0.8}$Sr$_{0.2...
9709294v1
1998-03-20
Transitions between Phases with Equal Wave Numbers in a Double Ising Spin Model. Application to Betaine Calcium Chloride Dihydrate
A Double Ising Spin model for uniaxially structurally modulated materials exhibits as a special feature phase transitions between phases with equal wave numbers but different pseudo spin configurations. The character of these `internal' transitions is investigated in mean field approximation, with the mean field transf...
9803252v1
1999-04-26
Magnon Damping by magnon-phonon coupling in Manganese Perovskites
Inelastic neutron scattering was used to systematically investigate the spin-wave excitations (magnons) in ferromagnetic manganese perovskites. In spite of the large differences in the Curie temperatures ($T_C$s) of different manganites, their low-temperature spin waves were found to have very similar dispersions with ...
9904372v1
1999-07-12
Quantum Hall Transitions in Field Induced Spin Density Wave Systems
Field Induced Spin Density Wave (FISDW) systems exhibit coexistence phases between well defined quantum Hall plateau phases with even integers 2N and 2N'. We show that a disordered coexistence region accounts for the observed peaks in the longitudinal resistivity as the field varies between plateaux. It also results in...
9907170v1
1999-07-19
Spin waves in a two dimensional p-wave superconductor: Sr$_2$RuO$_4$
We study spin excitations in a two dimensional p-wave superconductor with ${\vec \Delta} = {\hat d}({\hat k}_1 \pm i {\hat k}_2)$ symmetry in the context of the newly discovered superconducting Sr$_2$RuO$_4$. The polarization and spectrum of spin wave excitations are identified and their experimental consequences are d...
9907276v2
2001-05-31
Phase transition and spin-wave dispersion in quantum Hall bilayers at filling factor nu=1
We present an effective Hamiltonian for a bilayer quantum Hall system at filling factor $\nu=1$ neglecting charge fluctuations. Our model is formulated in terms of spin and pseudospin operators and is an exact representation of the system within the above approximation. We analyze its low-lying excitations in terms of ...
0105625v2
2001-08-24
Influence of disorder on the ferromagnetism in diluted magnetic semiconductors
Influence of disorder on the ferromagnetic phase transition in diluted (III,Mn)V semiconductors is investigated analytically. The regime of small disorder is addressed, and the enhancement of the critical temperature by disorder is found both in the mean field approximation and from the analysis of the zero temperature...
0108396v2
2001-10-16
Spin Waves, Phase Separation, and Interphase Boundaries in Double Exchange Magnets
We study a classical double exchange magnet with direct antiferromagnetic superexchange coupling, J, between the localized spins. It is shown that the de-stabilization of the ferromagnetic ground state with increasing J leads to phase separation; the latter always preempts the spin-wave instability (softening of the ma...
0110322v2
2002-05-08
Superconductor-to-Spin-Density-Wave Transition in Quasi-One-Dimensional Metals with Ising Anisotropy
We study a mechanism for superconductivity in quasi-one-dimensional materials with Ising anisotropy. In an isolated chain Ising anisotropy opens a spin gap; if inter-chain coupling is sufficiently weak, single particle hopping is suppressed and the physics of coupled chains is controlled by a competition between pair h...
0205166v1
2002-09-23
Rigorous Proof of Pseudospin Ferromagnetism in Two-Component Bosonic Systems with Component-Independent Interactions
For a two-component bosonic system, the components can be mapped onto a pseudo-spin degree of freedom with spin quantum number S=1/2. We provide a rigorous proof that for a wide-range of real Hamiltonians with component independent mass and interaction, the ground state is a ferromagnetic state with pseudospin fully po...
0209529v1
2003-02-24
Study of low-energy magnetic excitations in single-crystalline CeIn3 by inelastic neutron scattering
Inelastic neutron scattering experiments were performed on single crystals of the heavy-fermion compound CeIn$_{3}$ for temperatures below and above the N\'eel temperature, $T_N$. In the antiferromagnetically ordered phase, well-defined spin-wave excitations with a bandwidth of 2 meV are observed. The spin waves coexis...
0302487v1
2003-04-02
Current-induced transverse spin wave instability in a thin nanomagnet
We show that an unpolarized electric current incident perpendicular to the plane of a thin ferromagnet can excite a spin-wave instability transverse to the current direction if source and drain contacts are not symmetric. The instability, which is driven by the current-induced ``spin-transfer torque'', exists for one c...
0304069v2
2003-06-30
A chiral spin liquid wave function and the Lieb-Schulz-Mattis theorem
We study a chiral spin liquid wave function defined as a Gutwziller projected BCS state with a complex pairing function. After projection, spontaneous dimerization is found for any odd but finite number of chains, thus satisfying the Lieb-Schultz-Mattis theorem, whereas for even number of chains there is no dimerizatio...
0306732v1
2003-07-09
Photoemission study of the spin-density wave state in thin films of Cr
Angle-resolved photoemission (PE) was used to characterize the spin-density wave (SDW) state in thin films of Cr grown on W(110). The PE data were analysed using results of local spin density approximation layer-Korringa-Kohn-Rostoker calculations. It is shown that the incommensurate SDW can be monitored and important ...
0307196v1
2004-01-24
Static and Dynamic Properties of Antiferromagnetic Heisenberg Ladders: Fermionic versus Bosonic Approaches
In terms of spinless fermions via the Jordan-Wigner transformation along a snake-like path and spin waves modified so as to restore the sublattice symmetry, we investigate static and dynamic properties of two-leg antiferromagnetic Heisenberg ladders. The specific heat is finely reproduced by the spinless fermions, wher...
0401477v1
2004-06-05
Perturbative calculation of the spin-wave dispersion in a disordered double-exchange model
We study the spin-wave dispersion of localized spins in a disordered double-exchange model using the perturbation theory with respect to the strength of the disorder potential. We calculate the dispersion upto the next-leading order, and extensively examine the case of one-dimension. We show that in that case, disorder...
0406134v1
2005-04-26
Spin-Polarized Standing Waves in the Fermi Surface of a Ferromagnetic Thin Film
The spin-selective electron reflection at a ferromagnetic-paramagnetic interface is investigated using Fe films on a W(110) substrate. Angle-resolved photoemission of the majority and minority Fermi surfaces of the Fe film is used to probe standing wave formation. Intense quantum well states resulting from interfacial ...
0504670v1
2006-06-07
Pseudogap enhancement due to magnetic impurities in d-density waves
We study the effect of quantum magnetic impurities on d-wave spin density waves (d-SDW). The impurity spins are aligned coherently according to the spin space anisotropy of the condensate. Both the order parameter and transition temperature increases due to the coherent interplay between magnetic scatterers and d-SDW. ...
0606176v1
2006-09-13
Spin-wave dispersion in half-doped LaSrNiO
Recent neutron scattering measurements reveal spin and charge ordering in the half-doped nickelate, La$_{3/2}$ Sr$_{1/2}$ NiO$_4$. Many of the features of the magnetic excitations have been explained in terms of the spin waves of diagonal stripes with weak single-ion anisotropy. However, an optical mode dispersing away...
0609300v1
1999-10-12
Gravity Waves, Chaos, and Spinning Compact Binaries
Spinning compact binaries are shown to be chaotic in the Post-Newtonian expansion of the two body system. Chaos by definition is the extreme sensitivity to initial conditions and a consequent inability to predict the outcome of the evolution. As a result, the spinning pair will have unpredictable gravitational waveform...
9910040v3
1994-09-23
Motion of Spin-1/2 Particles in External Gravitational and Electromagnetic Fields
(Talk presented at the 7th Marcel Grossmann Meeting on General Relativity, Stanford, CA, July 24-30, 1994) We study the semi-classical limit of the solution of the Dirac equation in a background electromagnetic/gravitational plane wave. We show that the exact solution corresponding to an asymptotically fixed incoming m...
9409147v1
2003-06-28
On Equations for a Spin-2 Particle in External Gravitational Field
30-component, of the first order, equation for a spin 2 particle, equivalent to the second order Pauli-Fierz one, is generalized to presence of an external electromagnetic field as well as a curved background space-time geometry. The essential property of the generally covariant wave equation obtained is that here from...
0306286v1
2004-08-05
The novel aspect of hydrogen atom: the fine structure and spin can be derived by single component wavefunction
The fine structure of hydrogen energy was calculated by using the usual momentum-wavefunction relation directly, rather than establishing the well-known Dirac wave equation. As the results, the energy levels are completely the same as that of the Dirac wave equation, while the wavefunction is single component that is q...
0408025v1
2007-06-14
Spin-waves in a complex magnetic system: nonextensive approach
In this paper we analyze the spin-wave excitations (magnons) of an inhomogeneous spin system within the Boltzmann-Gibbs framework and then connect the results with the nonextensive approach (in the sense of Tsallis statistics). Considering an equivalence between those two frameworks, we could connect the entropic param...
0706.2201v2
2009-06-30
Quantum phase transition of the 103mRh spin-density wave
We induce a quantum phase transition of the 103mRh excitation at the critical density of 10^{12} cm^{-3} by bremsstrahlung pumping at 300 K. A massive 103mRh spin-density wave carrying a spin current moves on the identical 103Rh matrix like a quantum fluid. The collapse-and-revival spectral evolution indicates that the...
0906.5417v1
2009-10-15
Dixon's extended bodies and impulsive gravitational waves
The "reaction" of an extended body to the passage of an exact plane gravitational wave is discussed following Dixon's model. The analysis performed shows several general features, e.g. even if initially absent, the body acquires a spin induced by the quadrupole structure, the center of mass moves from its initial posit...
0910.2846v1
2010-11-04
Spin wave calculation of the field-dependent magnetization pattern around an impurity in Heisenberg antiferromagnets
We consider the magnetic-field dependent spatial magnetization pattern around a general impurity embedded in a Heisenberg antiferromagnet using both an analytical and a numerical spin wave approach. The results are compared to quantum Monte Carlo simulations. The decay of the magnetization pattern away from the impurit...
1011.1271v1
2010-11-15
Study of the Spin-weighted Spheroidal Equation in the Case of s=1
We present series study of using the method of super-symmetric quantum mechanics(SUSYQM) solving the spin-weighted spheroidal wave equation. In this paper, we obtain the first four terms of super-potential of the spin-weighted spheroidal wave equation in the case of s=1. These results may help summary the general form ...
1011.4045v1
2010-11-19
Spin waves in magnetic quantum wells with Coulomb interaction and $sd$ exchange coupling
We theoretically describe the spin excitation spectrum of a two dimensional electron gas embedded in a quantum well with localized magnetic impurities. Compared to the previous work, we introduce equations that allow to consider the interplay between the Coulomb interaction of delocalized electrons and the $sd$ exchang...
1011.4422v1
2011-04-01
Spin waves cause non-linear friction
Energy dissipation is studied for a hard magnetic tip that scans a soft magnetic substrate. The dynamics of the atomic moments are simulated by solving the Landau-Lifshitz-Gilbert (LLG) equation numerically. The local energy currents are analysed for the case of a Heisenberg spin chain taken as substrate. This leads to...
1104.0197v2
2011-07-05
Magnetic field and quark matter in the core
Magnetic properties of quark matter are discussed in the light of the observation of pulsars. Our works about spontaneous spin polarization and spin density wave are reviewed and their implications on compact-star phenomena are discussed. In particular, the former subject may be directly related to the origin of strong...
1107.0807v2
2011-09-02
Gravitational Waves and the Maximum Spin Frequency of Neutron Stars
In this Letter we re-examine the idea that gravitational waves are required as a braking mechanism to explain the observed maximum spin-frequency of neutron stars. We show that for millisecond X-ray pulsars, the existence of spin equilibrium as set by the disk/magnetosphere interaction is sufficient to explain the obse...
1109.0536v1
2011-12-13
Spectral properties of one-dimensional spiral spin density wave states
We provide a full characterization of the spectral properties of spiral spin density wave (SSDW) states which emerge in one-dimensional electron systems coupled to localized magnetic moments or quantum wires with spin-orbit interactions. We derive analytic results for the spectral function, local density of states and ...
1112.3045v2
2012-03-07
Temperature Induced Spin Density Wave in Magnetic Doped Topological Insulators
We study the magnetic properties of topological insulators doped with isoelectronic magnetic impurities. We obtain that at zero temperature the impurities order ferromagnetically, but when raising the temperature the topological insulator undergoes a first order phase transition to a spin density wave phase before the ...
1203.1436v2
2012-03-13
Spin induced multipole moments for the gravitational wave amplitude from binary inspirals to 2.5 Post-Newtonian order
Using the NRGR effective field theory formalism we calculate the remaining source multipole moments necessary to obtain the spin contributions to the gravitational wave amplitude to 2.5 Post-Newtonian (PN) order. We also reproduce the tail contribution to the waveform linear in spin at 2.5PN arising from the nonlinear ...
1203.2962v2
2012-06-15
Kinks and waterfalls as signatures of competing order in angle-resolved photoemission spectra of La_{2-x}Sr_xCuO_4
We show that the so-called kinks and waterfalls observed in angle-resolved photoemission spectra of La2-xSrxCuO4, a prototypical high-Tc superconducting cuprate, result from the coupling of quasiparticles with two distinct nearly critical collective modes with finite characteristic wave vectors, typical of charge and s...
1206.3427v1
2012-12-17
Electromagnetic soliton-particle with spin and magnetic moment
Electromagnetic soliton-particle with both quasi-static and quick-oscillating wave parts is considered. Its mass, spin, charge, and magnetic moment appear naturally when the interaction with distant solitons is considered. The substantiation of Dirac equation for the wave part of the interacting soliton-particle is giv...
1212.4468v1
2013-03-31
Semi classical modeling of isotropic Non-Heisenberg magnets for spin S=1 and linear quadrupole excitation dynamics
In this paper, equations describing one-dimensional Non-Heisenberg model are studied by use of generalized coherent states in real parameterization and then dissipative spin wave equation for dipole and quadrupole branches is obtained if there is a small linear excitation from the ground state. Finally, it is shown tha...
1304.0245v1
2013-04-02
Asymptotic spectrum of the oblate spin-weighted spheroidal harmonics: a WKB analysis
Spin-weighted spheroidal harmonics play a central role in the mathematical description of diverse physical phenomena, including black-hole perturbation theory and wave scattering. We present a novel and compact derivation of the asymptotic eigenvalues of these important functions. Our analysis is based on a simple tric...
1304.0529v1
2013-09-19
Equivariant and self-similar standing waves for a Hamiltonian hyperbolic-hyperbolic spin-field system
In this paper we study the existence of special symmetric solutions to a Hamiltonian hyperbolic-hyperbolic coupled spin-field system, where the spins are maps from $\mathbb R^{2+1}$ into the sphere $\S^2$ or the pseudo-sphere $\H^2$. This model was introduced in \cite{Martina} and it is also known as the {\it hyperboli...
1309.5066v2
2013-10-12
Inversion Phenomena of the Anisotropies of the Hamiltonian and the Wave Function in Quantum Spin Chains
We investigate the inversion phenomena between the XXZ anisotropies of the Hamiltonian and the wave function in quantum spin chains. We focus on the S=1/2 geometrically frustrated 3-leg ladder system with the XXZ interaction anisotropy. By use of the degenerate perturbation theory from the strong rung coupling limit, w...
1310.3394v1
2014-05-07
Spin structure factor and quantum phases of frustrated spin-1/2 chains
The static structure factor S(q) of frustrated spin-1/2 chains with isotropic exchange and a singlet ground state (GS) diverges at wave vector q_m when the GS has quasi-long-range order (QLRO) with periodicity 2\pi/q_m but S(q_m) is finite in bond-order-wave (BOW) phases with finite-range spin correlations. Exact diago...
1405.1578v1
2014-08-21
Scattering by an electromagnetic radiation field
Motion of test particles in the gravitational field associated with an electromagnetic plane wave is investigated. The interaction with the radiation field is modeled by a force term {\it \`a la} Poynting-Robertson entering the equations of motion given by the 4-momentum density of radiation observed in the particle's ...
1408.4958v1
2014-11-14
Magnetic order and spin excitations in layered Heisenberg antiferromagnets with compass-model anisotropies
The spin-wave excitation spectrum, the magnetization, and the N\'{e}el temperature for the quasi-two-dimensional spin-1/2 antiferromagnetic Heisenberg model with compass-model interaction in the plane proposed for iridates are calculated in the random phase approximation. The spin-wave spectrum agrees well with data of...
1411.3920v2
2015-04-03
Solitons in a continuous classical Haldane-Shastry spin chain
Motivated by Polychronakos' discovery that solitons exist in the hydrodynamic equations of continuum version of the Calogero model, we seek solitons in the classical dynamics of a continuum version of the Haldane-Shastry spin chain. We have obtained analytic multi-lump solitary wave solutions for our spin-field equatio...
1504.00873v1
2016-01-30
Low-Temperature Spin-Wave Approximation for the Heisenberg Ferromagnet
We study the low temperature thermodynamics of the quantum Heisenberg ferromagnet in three dimension for any value of the spin $ S \geq 1/2 $. We report on a rigorous proof of the validity of the spin-wave approximation for the excitation spectrum, at the level of the first non-trivial contribution to the free energy a...
1602.00155v1
2019-09-10
Enhanced Detectability of Spinning Primordial Black Holes
Primordial black holes which are produced during an epoch of matter domination are expected to spin rapidly. It is shown that this leads to an enhancement of the detectability of the stochastic gravitational-wave background from their mergers. For a specific model, we explicitly demonstrate that this yields a $50\,\%$ ...
1909.04742v2
2020-07-30
Derivation of the Half-Wave Maps Equation from Calogero--Moser Spin Systems
We prove that the energy-critical half-wave maps equation \[ \partial_t \mathbf{S} =\mathbf{S} \times |\nabla| \mathbf{S}, \quad (t,x) \in \mathbb{R} \times \mathbb{T} \] arises as an effective equation in the continuum limit of completely integrable Calogero-Moser classical spin systems with inverse square $1/r^2$ int...
2007.15323v1
2020-12-02
Effects of exchange distortions in the magnetic Kagome lattice
This study examines the effect of distorted triangular magnetic interactions in the Kagome lattice. Using a Holstein-Primakoff expansion, we determine the analytical solutions for classical energies and the spin-wave modes for various magnetic configurations. By understanding the magnetic phase diagram, we characterize...
2012.00910v1
2021-01-18
Quantum fluctuation effects on the ordered Moments in a two dimensional frustrated ferrimagnet
We propose a novel two-dimensional (2D)frustrated quantum spin-1/2 anisotropic Heisenberg model with alternating ferromagnetic and antiferromagnetic magnetic chains along one direction and antiferromagnetic interactions along the other. The (mean-field) ground state is ferrimagnetic in certain range of the interaction ...
2101.07300v1
2021-12-27
Penrose limit of MNa solution and spin chains in three-dimensional field theories
In three dimensions, a theory with spontaneous breaking of supersymmetry was described holographically by the Maldacena-Nastase (MNa) solution. We revisit the issue of its Penrose limit, and compare the resulting pp wave and its string eigenstates to a sector of the theory on 5-branes reduced on $S^3$, and a spin chain...
2112.13802v2
2022-04-19
Spin correlations in the frustrated ferro-antiferromagnet SrZnVO(PO4)2 near saturation
Single crystal elastic and inelastic neutron scattering experiments are performed on the frustrated ferro-antiferromagnet SrZnVO(PO4)2 in high magnetic fields. The fully polarized state, the presaturation phase and the columnar-antiferromagnetic phase just bellow the presaturation phase were investigated. The observed ...
2204.08778v2
2023-03-20
Electron Wave Spin in Excited States
The wave spin of an electron can be fully characterized by the current density calculated from the exact four-spinor solution of the Dirac equation. In the excited states of the electron in a magnetic field-free quantum well, the current density has a multiple vortex topology. The interaction of the current with a magn...
2303.10855v1
2023-09-09
Teukolsky-like equations with various spins in spherically symmetric spacetime
We study the wave equations with various spins on the background of the general spherically symmetric spacetime. We obtain the unified expression of the Teukolsky-like master equations and the corresponding radial equations with the general spins. We also discuss the gauge dependence in the gravitational-wave equations...
2309.04758v2
2015-12-24
Shedding Light on Diphoton Resonances
The experimental and theoretical implications of heavy digauge boson resonances that couple to, or are comprised of, new charged and strongly interacting matter are investigated. Observation and measurement of ratios of the resonant digauge boson channels $WW$, $ZZ$, $\gamma \gamma$, $Z \gamma$, and $gg$ in the form of...
1512.07733v3
2008-05-05
On-chip Integration of High-Frequency Electron Paramagnetic Resonance Spectroscopy and Hall-Effect Magnetometry
A sensor that integrates high sensitivity micro-Hall effect magnetometry and high-frequency electron paramagnetic resonance spectroscopy capabilities on a single semiconductor chip is presented. The Hall-effect magnetometer was fabricated from a two dimensional electron gas GaAs/AlGaAs heterostructure in the form of a ...
0805.0565v1
2021-07-12
Avalanches and many-body resonances in many-body localized systems
We numerically study both the avalanche instability and many-body resonances in strongly-disordered spin chains exhibiting many-body localization (MBL). We distinguish between a finite-size/time MBL regime, and the asymptotic MBL phase, and identify some "landmarks" within the MBL regime. Our first landmark is an estim...
2107.05642v3
1998-10-14
Spin relaxation in Mn12-acetate
We present a comprehensive derivation of the magnetization relaxation in a Mn12-acetate crystal based on thermally assisted spin tunneling induced by quartic anisotropy and weak transverse magnetic fields. The overall relaxation rate as function of the magnetic field is calculated and shown to agree well with data incl...
9810156v3
2000-02-01
Resonant Spin Excitation in an Overdoped High Temperature Superconductor
An inelastic neutron scattering study of overdoped Bi_2Sr_2CaCu_2O_{8+\delta} $ (T_c = 83 K) has revealed a resonant spin excitation in the superconducting state. The mode energy is E_res=38 meV, significantly lower than in optimally doped Bi_2Sr_2CaCu_2O_{8+\delta} (T_c = 91 K, E_ res =43 meV). This observation, which...
0002013v3
2000-09-05
Where is the pi particle?
We discuss the interplay of particle-particle and particle-hole spin-triplet channels in high-T_c superconductors using a quasiparticle dispersion motivated by angle-resolved photoemission. Within a generalized RPA, we find a well defined antibound state of two holes, the pi resonance of Demler and Zhang, as well as a ...
0009072v1
2005-07-29
Resonant Pair Exchange and Percolation in the Disordered Hubbard Model
We show that the effect of disorder on a Mott-Hubbard insulator of interacting electrons produces a quantum phase transition from an antiferromagnetic to a paramagnetic phase governed by a percolation of the singly occupied weakly disordered sites. Near the transition, we propose that a new type of defect, formed by th...
0507701v1
1998-12-16
Effects of magnetohydrodynamics matter density fluctuations on the solar neutrino resonant spin-flavor precession
Taking into account the stringent limits from helioseismology observations on possible matter density fluctuations described by magnetohydrodynamics theory, we find the corresponding time variations of solar neutrino survival probability due to the resonant spin-flavor precession phenomenon with amplitude of order O(10...
9812390v1
1999-06-28
Influence of Non-Resonant Effects on the Dynamics of Quantum Logic Gates at Room Temperature
We study numerically the influence of non-resonant effects on the dynamics of a single $\pi$-pulse quantum CONTROL-NOT (CN) gate in a macroscopic ensemble of fo ur-spin molecules at room temperature. The four nuclear spins in each molecule r epresent a four-qubit register. The qubits are ``labeled'' by the characterist...
9906109v1
2007-10-22
Microwave band on-chip coil technique for single electron spin resonance in a quantum dot
Microwave band on-chip microcoils are developed for the application to single electron spin resonance measurement with a single quantum dot. Basic properties such as characteristic impedance and electromagnetic field distribution are examined for various coil designs by means of experiment and simulation. The combined ...
0710.3986v2
2008-10-10
Deciphering the spin of new resonances in Higgsless models
We study the potential of the CERN Large Hadron Collider (LHC) to probe the spin of new massive vector boson resonances predicted by Higgsless models. We consider its production via weak boson fusion which relies only on the coupling between the new resonances and the weak gauge bosons. We show that the LHC will be abl...
0810.1952v3
2009-01-31
Density of States in the Magnetic Ground State of the Friedel-Anderson Impurity
By applying a magnetic field whose Zeeman energy exceeds the Kondo energy by an order of magnitude the ground state of the Friedel-Anderson impurity is a magnetic state. In recent years the author introduced the Friedel Artificially Inserted Resonance (FAIR) method to investigate impurity properties. Within this FAIR a...
0902.0033v1