publicationDate stringlengths 1 2.79k | title stringlengths 1 36.5k ⌀ | abstract stringlengths 1 37.3k ⌀ | id stringlengths 9 47 |
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2019-08-21 | Generalized Metric Repair on Graphs | Many modern data analysis algorithms either assume or are considerably more
efficient if the distances between the data points satisfy a metric. These
algorithms include metric learning, clustering, and dimension reduction. As
real data sets are noisy, distances often fail to satisfy a metric. For this
reason, Gilbert ... | 1908.08411v1 |
2019-09-19 | Parameterized Complexity of Manipulating Sequential Allocation | The sequential allocation protocol is a simple and popular mechanism to
allocate indivisible goods, in which the agents take turns to pick the items
according to a predefined sequence. While this protocol is not strategy-proof,
it has been shown recently that finding a successful manipulation for an agent
is an NP-hard... | 1909.08920v4 |
2019-11-06 | Doppler Spectrum Classification with CNNs via Heatmap Location Encoding and a Multi-head Output Layer | Spectral Doppler measurements are an important part of the standard
echocardiographic examination. These measurements give important insight into
myocardial motion and blood flow providing clinicians with parameters for
diagnostic decision making. Many of these measurements can currently be
performed automatically with... | 1911.02407v2 |
2020-01-02 | The Effect of Treatment-Related Deaths and "Sticky" Diagnoses on Recorded Prostate Cancer Mortality | Background: Although recorded cancer mortality should include both deaths
from cancer and deaths from cancer treatment, there is evidence suggesting that
the measure may be incomplete. To investigate the completeness of recorded
prostate cancer mortality, we compared other-cause (non-prostate cancer)
mortality in men f... | 2001.00492v1 |
2020-06-09 | Elemental Abundances in M31: Iron and Alpha Element Abundances in M31's Outer Halo | We present [Fe/H] and [$\alpha$/Fe] abundances, derived using spectral
synthesis techniques, for stars in M31's outer stellar halo. The 21 [Fe/H]
measurements and 7 [$\alpha$/Fe] measurements are drawn from fields ranging
from 43 to 165 kpc in projected distance from M31. We combine our measurements
with existing liter... | 2006.05430v1 |
2020-11-11 | Unique Decoding of Explicit $ε$-balanced Codes Near the Gilbert-Varshamov Bound | The Gilbert-Varshamov bound (non-constructively) establishes the existence of
binary codes of distance $1/2 -\epsilon$ and rate $\Omega(\epsilon^2)$ (where
an upper bound of $O(\epsilon^2\log(1/\epsilon))$ is known). Ta-Shma [STOC
2017] gave an explicit construction of $\epsilon$-balanced binary codes, where
any two di... | 2011.05500v1 |
2021-03-30 | Equivalence between Sobolev spaces of first-order dominating mixed smoothness and unanchored ANOVA spaces on $\mathbb{R}^d$ | We prove that a variant of the classical Sobolev space of first-order
dominating mixed smoothness is equivalent (under a certain condition) to the
unanchored ANOVA space on $\mathbb{R}^d$, for $d \geq 1$. Both spaces are
Hilbert spaces involving weight functions, which determine the behaviour as
different variables ten... | 2103.16075v3 |
2021-06-13 | Advantages of a semi-implicit scheme over a fully implicit scheme for Landau-Lifshitz-Gilbert equation | Magnetization dynamics in magnetic materials is modeled by the
Landau-Lifshitz-Gilbert (LLG) equation. In the LLG equation, the length of
magnetization is conserved and the system energy is dissipative. Implicit and
semi-implicit schemes have been used in micromagnetics simulations due to their
unconditional numerical ... | 2106.06936v1 |
2021-08-06 | A second-order semi-implicit method for the inertial Landau-Lifshitz-Gilbert equation | Recent theoretical and experimental advances show that the inertia of
magnetization emerges at sub-picoseconds and contributes to the ultrafast
magnetization dynamics which cannot be captured intrinsically by the LLG
equation. Therefore, as a generalization, the inertial Landau-Lifshitz-Gilbert
(iLLG) equation is propo... | 2108.03060v1 |
2021-09-08 | Flares, Rotation, and Planets of the AU Mic System from TESS Observations | AU Mic is a young ($\sim$24 Myr), pre-Main Sequence M~dwarf star that was
observed in the first month of science observations of the Transiting Exoplanet
Survey Satellite (TESS) and re-observed two years later. This target has
photometric variability from a variety of sources that is readily apparent in
the TESS light ... | 2109.03924v1 |
2021-10-29 | The TREX Survey: Kinematical Complexity Throughout M33's Stellar Disk and Evidence for a Stellar Halo | We present initial results from a large spectroscopic survey of stars
throughout M33's stellar disk. We analyze a sample of 1667 red giant branch
(RGB) stars extending to projected distances of $\sim 11$ kpc from M33's center
($\sim 18$ kpc, or $\sim 10$ scale lengths, in the plane of the disk). The
line-of-sight veloc... | 2110.15773v1 |
2021-11-23 | Magnetism in Metastable and Annealed Compositionally Complex Alloys | Compositionally complex materials (CCMs) present a potential paradigm shift
in the design of magnetic materials. These alloys exhibit long-range structural
order coupled with limited or no chemical order. As a result, extreme local
environments exist with a large opposing magnetic energy term, which can
manifest large ... | 2111.12188v1 |
2021-11-23 | Controlling magnetic configuration in soft-hard bilayers probed by polarized neutron reflectometry | Hard/soft magnetic bilayer thin films have been widely used in data storage
technologies and permanent magnet applications. The magnetic configuration and
response to temperatures and magnetic fields in these heterostructures are
considered to be highly dependent on the interfacial coupling. However, the
intrinsic prop... | 2111.12191v1 |
2022-01-18 | On-demand electrical control of spin qubits | Once called a "classically non-describable two-valuedness" by Pauli , the
electron spin is a natural resource for long-lived quantum information since it
is mostly impervious to electric fluctuations and can be replicated in large
arrays using silicon quantum dots, which offer high-fidelity control.
Paradoxically, one ... | 2201.06679v2 |
2022-04-28 | Anti-microbial properties of a multi-component alloy | High traffic touch surfaces such as doorknobs, countertops, and handrails can
be transmission points for the spread of pathogens, emphasizing the need to
develop materials that actively self-sanitize. Metals are frequently used for
these surfaces due to their durability, but many metals also possess
antimicrobial prope... | 2205.00886v1 |
2022-05-11 | Models of Advance Recording Systems: A Multi-timescale Micromagnetic code for granular thin film magnetic recording systems | Micromagnetic modelling provides the ability to simulate large magnetic
systems accurately without the computational cost limitation imposed by
atomistic modelling. Through micromagnetic modelling it is possible to simulate
systems consisting of thousands of grains over a time range of nanoseconds to
years, depending u... | 2205.05263v1 |
2023-01-03 | Measuring Physical and Electrical Parameters in Free-Living Subjects: Motivating an Instrument to Characterize Analytes of Clinical Importance in Blood Samples | Significance: A path is described to increase the sensitivity and accuracy of
body-worn devices used to monitor patient health. This path supports improved
health management. A wavelength-choice algorithm developed at Mayo demonstrates
that critical biochemical analytes can be assessed using accurate optical
absorption... | 2301.00938v2 |
2023-01-09 | A Second Earth-Sized Planet in the Habitable Zone of the M Dwarf, TOI-700 | We report the discovery of TOI-700 e, a 0.95 R$_\oplus$ planet residing in
the Optimistic Habitable Zone (HZ) of its host star. This discovery was enabled
by multiple years of monitoring from NASA's Transiting Exoplanet Survey
Satellite (TESS) mission. The host star, TOI-700 (TIC 150428135), is a nearby
(31.1 pc), inac... | 2301.03617v1 |
2023-01-17 | Introduction to Non-Invasive Current Estimation (NICE) | It is notoriously difficult to measure instantaneous supply current to a
device such as an ASIC, FPGA, or CPU without also affecting the instantaneous
supply voltage and compromising the operation of the device [21]. For decades
designers have relied on rough estimates of dynamic load currents that
stimulate a designed... | 2301.10237v1 |
2023-02-08 | Weighted Edit Distance Computation: Strings, Trees and Dyck | Given two strings of length $n$ over alphabet $\Sigma$, and an upper bound
$k$ on their edit distance, the algorithm of Myers (Algorithmica'86) and Landau
and Vishkin (JCSS'88) computes the unweighted string edit distance in
$\mathcal{O}(n+k^2)$ time. Till date, it remains the fastest algorithm for
exact edit distance ... | 2302.04229v1 |
2023-03-09 | Zonostrophic instabilities in magnetohydrodynamic Kolmogorov flow | This paper concerns the stability of Kolmogorov flow u = (0, sin x) in the
infinite (x,y)-plane. A mean magnetic field of strength B0 is introduced and
the MHD linear stability problem studied for modes with wave-number k in the
y-direction, and Bloch wavenumber l in the x-direction. The parameters
governing the proble... | 2303.05212v1 |
2023-03-30 | Fate of entanglement in magnetism under Lindbladian or non-Markovian dynamics and conditions for their transition to Landau-Lifshitz-Gilbert classical dynamics | It is commonly assumed in spintronics and magnonics that localized spins
within antiferromagnets are in the N\'{e}el ground state (GS), as well as that
such state evolves, when pushed out of equilibrium by current or external
fields, according to the Landau-Lifshitz-Gilbert (LLG) equation viewing
localized spins as cla... | 2303.17596v3 |
2024-02-07 | Item-Level Heterogeneous Treatment Effects of Selective Serotonin Reuptake Inhibitors (SSRIs) on Depression: Implications for Inference, Generalizability, and Identification | In analysis of randomized controlled trials (RCTs) with patient-reported
outcome measures (PROMs), Item Response Theory (IRT) models that allow for
heterogeneity in the treatment effect at the item level merit consideration.
These models for ``item-level heterogeneous treatment effects'' (IL-HTE) can
provide more accur... | 2402.04487v1 |
1995-02-16 | Lyman alpha Emission from High-Redshift Galaxies | We summarise the results of a deep search for Lyman alpha emission from
star-forming regions associated with damped Lyman alpha absorption systems and
conclude that the Lyman alpha luminosity of high redshift galaxies is generally
less than 10^(42) erg/s . We also present a newly discovered case, in the field
of the QS... | 9502076v1 |
1995-10-12 | Limits on diffusive shock acceleration in dense and incompletely ionised media | The limits imposed on diffusive shock acceleration by upstream ion-neutral
Alfven wave damping, and by ionisation and Coulomb losses of low energy
particles, are calculated. Analytic solutions are given for the steady upstream
wave excitation problem with ion-neutral damping and the resulting escaping
upstream flux cal... | 9510066v2 |
1995-11-28 | Damping of GRR instability by direct URCA reactions | The role of direct URCA reactions in damping of the gravitational radiation
driven instability is discussed. The temperature at which bulk viscosity
suppresses completely this instability is calculated.
The results are obtained analytically using recent calculations performed in
the case of bulk viscosity due to the ... | 9511136v1 |
1997-10-31 | Abundances in Damped Lyman-alpha Systems and Chemical Evolution of High Redshift Galaxies | Recent abundance measurements in damped Lyman-alpha galaxies, supplemented
with unpublished Keck observations, are discussed. The metallicity distribution
with cosmic time is examined for clues about the degree of enrichment, the
onset of initial star formation, and the nature of the galxies. The relative
abundances of... | 9710370v1 |
1998-05-08 | Exploring the Damped Lyman-alpha Clouds with AXAF | The High Energy Transmission Grating (HETG) Spectrometer on the Advanced
X-ray Astrophysics Facility (AXAF) (scheduled for launch in August, 1998) will
provide a new tool for the study of absorption in the X-ray spectra of high
redshift quasars due to the material along the line of sight. In this paper we
try to explor... | 9805110v1 |
1998-05-28 | Photon Damping of Waves in Accretion Disks | MHD turbulence is generally believed to have two important functions in
accretion disks: it transports angular momentum outward, and the energy in its
shortest wavelength modes is dissipated into the heat that the disks radiate.
In this paper we examine a pair of mechanisms which may play an important role
in regulatin... | 9805358v1 |
1998-06-11 | Damping of differential rotation in neutron stars | We derive the transport relaxation times for quasiparticle-vortex scattering
processes via nuclear force, relevant for the damping of differential rotation
of superfluids in the quantum liquid core of a neutron star. The proton
scattering off the neutron vortices provides the dominant resistive force on
the vortex latt... | 9806156v1 |
1999-03-10 | Elemental abundances at early times: the nature of Damped Lyman-alpha systems | The distribution of element abundances with redshift in Damped Ly-alpha (DLA)
systems can be adequately reproduced by the same model reproducing the halo and
disk components of the Milky Way Galaxy at different galactocentric distances:
DLA systems are well represented by normal spiral galaxies in their early
evolution... | 9903150v1 |
1999-07-26 | Are Damped Ly-alpha Systems Large, Galactic Disks ? | The hypothesis that the Damped Ly-alpha systems (DLAs) are large, galactic
disks (Milky Way sized) is tested by confronting predictions of models of the
formation and evolution of (large) disk galaxies with observations, in
particular the Zinc abundance distribution with neutral hydrogen column density
found for DLAs. ... | 9907349v1 |
1999-08-26 | Oscillator Strengths and Damping Constants for Atomic Lines in the J and H Bands | We have built a line list in the near-infrared J and H bands (1.00-1.34,
1.49-1.80 um) by gathering a series of laboratory and computed line lists.
Oscillator strengths and damping constants were computed or obtained by fitting
the solar spectrum.
The line list presented in this paper is, to our knowledge, the most c... | 9908296v1 |
1999-11-25 | Probing Solar Convection | In the solar convection zone acoustic waves are scattered by turbulent sound
speed fluctuations. In this paper the scattering of waves by convective cells
is treated using Rytov's technique. Particular care is taken to include
diffraction effects which are important especially for high-degree modes that
are confined to... | 9911469v1 |
1999-12-14 | The Gas Reservoir for present day Galaxies : Damped Ly-alpha Absorption Systems | We present results from an ongoing search for galaxy counterparts of a
subgroup of Quasar Absorption Line Systems called Damped Ly-alpha Absorbers
(DLAs). DLAs have several characteristics that make them essential in the
process of understanding how galaxies formed in the early universe and evolved
to the galaxies we s... | 9912268v1 |
2000-06-22 | Nuclear Reaction Rates in a Plasma: The Effect of Highly Damped Modes | The fluctuation-dissipation theorem is used to evaluate the screening factor
of nuclear reactions due to the electromagnetic fluctuations in a plasma. We
show that the commonly used Saltpeter factor is obtained if only fluctuations
near the plasma eigenfrequency are assumed to be important (\omega \sim
\omega_{pe}\ll T... | 0006326v1 |
2000-09-06 | The Cosmological Evolution of Quasar Damped Lyman-Alpha Systems | We present results from an efficient, non-traditional survey to discover
damped Lyman-alpha (DLA) absorption-line systems with neutral hydrogen column
densities N(HI)>2x10^{20} atoms cm^{-2} and redshifts z<1.65. Contrary to
previous studies at higher redshift that showed a decrease in the cosmological
mass density of ... | 0009098v1 |
2001-01-13 | Measuring Feedback in Damped Lyman Alpha Systems | We measure feedback (heating rates) in damped Lyman alpha systems from the
cooling rate of the neutral gas. Since cooling occurs through [C II] 158 micron
emission, we infer cooling from C II^{*} 1335.7 absorption lines detected with
HIRES on the Keck I telescope. The inferred heating rates are about 30 times
lower tha... | 0101218v1 |
2001-04-18 | The First Detection of Cobalt in a Damped Lyman Alpha System | We present the first ever detection of Cobalt in a Damped Lyman Alpha system
(DLA) at z = 1.92. In addition to providing important clues to the star
formation history of these high redshift galaxies, we discuss how studying the
Co abundance in DLAs may also help to constrain models of stellar
nucleosynthesis in a regim... | 0104301v1 |
2001-05-09 | Nuclear reaction rates and energy in stellar plasmas : The effect of highly damped modes | The effects of the highly damped modes in the energy and reaction rates in a
plasma are discussed. These modes, with wavenumbers $k \gg k_{D}$, even being
only weakly excited, with less than $k_{B}T$ per mode, make a significant
contribution to the energy and screening in a plasma. When the de Broglie
wavelength is muc... | 0105153v1 |
2001-07-03 | The HI Content and Extent of Low Surface Brightness Galaxies - Could LSB Galaxies be Responsible for Damped Ly-alpha Absorption? | Low surface brightness galaxies, those galaxies with a central surface
brightness at least one magnitude fainter than the night sky, are often not
included in discussions of extragalactic gas at z < 0.1. In this paper we
review many of the properties of low surface brightness galaxies, including
recent studies which in... | 0107064v1 |
2001-09-10 | H_2 molecules in damped systems | Damped Lyman alpha systems seen in the spectra of high-z QSOs arise in
high-density neutral gas in which molecular hydrogen (H_2) should be
conspicuous. Systematic searches to detect the H_2 lines redshifted into the
Lyman alpha forest at <3400\AA are now possible thanks to the unique
capabilities of UVES on the VLT. H... | 0109155v1 |
2001-10-23 | A scaling law of interstellar depletions as a tool for abundance studies of Damped Ly alpha systems | An analytical expression is presented that allows dust depletions to be
estimated in different types of interstellar environments, including Damped Ly
alpha systems. The expression is a scaling law of a reference depletion pattern
and takes into account the possibility that the dust chemical composition may
vary as a f... | 0110499v1 |
2002-09-23 | Outflows in Galaxies and Damped Ly-alpha System | Although quasar absorbers, and in particular Damped Lyman-alpha systems
(DLAs) have proven a valuable tool to study the early Universe, their exact
nature is so far poorly constrained. It has been suggested that outflows in
galaxies might account for at least part of the DLA population. Observational
evidences and mode... | 0209463v1 |
2004-03-15 | The Damping Wing of the Gunn-Peterson Absorption and Lyman-Alpha Emitters in the Pre-Reionization Era | We use a numerical simulation of cosmological reionization to estimate the
likelihood of detecting Lyman-alpha emitting galaxies during the
pre-reionization era. We show that it is possible to find galaxies even at z~9
that are barely affected by the dumping wing of the Gunn-Peterson absorption
from the neutral IGM out... | 0403345v1 |
2005-05-28 | Cosmic ray transport in MHD turbulence | Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call
for revisions in the picture of cosmic ray transport. In this paper we use
recently obtained scaling laws for MHD modes to obtain the scattering frequency
for cosmic rays. We account for the turbulence cutoff arising from both
collisional and... | 0505575v1 |
2005-06-09 | Phantom damping of matter perturbations | Cosmological scaling solutions are particularly important in solving the
coincidence problem of dark energy. We derive the equations of sub-Hubble
linear matter perturbations for a general scalar-field Lagrangian--including
quintessence, tachyon, dilatonic ghost condensate and k-essence--and solve them
analytically for... | 0506222v1 |
2005-06-22 | A Damped Ly-alpha Absorption-line System in an Apparent Void at Redshift 2.38 | We study the contents of an apparent void in the distribution of Ly-alpha
emitting galaxies at redshift 2.38. We show that this void is not empty, but
contains a damped Ly-alpha absorption-line system, seen in absorption against
background QSO 2138-4427. Imaging does not reveal any galaxy associated with
this absorptio... | 0506525v1 |
2005-08-08 | Fluorescence in damp air and comments on the radiative life time | Photon yields in damp air excited by an electron using a Sr90 $\beta$ source
are compared withthose in dry air. Water vapors considerably reduce the yields,
however, a further study is needed to evaluate the effects on the energy
estimation of ultrahigh-energy cosmic rays. The relation of fluorescence
efficiency to the... | 0508183v1 |
2006-08-17 | Electron thermal conductivity owing to collisions between degenerate electrons | We calculate the thermal conductivity of electrons produced by
electron-electron Coulomb scattering in a strongly degenerate electron gas
taking into account the Landau damping of transverse plasmons. The Landau
damping strongly reduces this conductivity in the domain of ultrarelativistic
electrons at temperatures belo... | 0608371v1 |
2006-09-19 | Dust, Metals and Diffuse Interstellar Bands in Damped Lyman Alpha Systems | Although damped Lyman alpha (DLA) systems are usually considered metal-poor,
it has been suggested that this could be due to observational bias against
metal-enriched absorbers. I review recent surveys to quantify the particular
issue of dust obscuration bias and demonstrate that there is currently no
compelling observ... | 0609530v1 |
2006-11-08 | Comments on Viscous Damping of Non-Adiabatic MHD Waves in an Unbounded Solar Coronal Plasma by Kumar and Kumar | Considering thermal conduction, compressive viscosity and optically thin
radiation as damping mechanisms for MHD waves, we derive a six-order general
dispersion relation. We point out a fundamental flaw in the derivation of
five-order dispersion relation by Kumar and Kumar (2006) who adopt as a basis
vector. The correc... | 0611252v2 |
2007-01-10 | Non-gaussianity in fluctuations from warm inflation | The scalar mode density perturbations in a the warm inflationary scenario are
analysed with a view to predicting the amount of non-gaussianity produced by
this scenario. The analysis assumes that the inflaton evolution is strongly
damped by the radiation, with damping terms that are temperature independent.
Entropy flu... | 0701302v2 |
1998-05-22 | WKB for a damped spin | The master equation for a damped spin well known from the theory of
superradiance, is written as a finite-difference equation and solved by a
WKB-like method. The propagator thus obtained looks like the van Vleck
propagator of a certain classical Hamiltonian system with one degree of
freedom. A new interpretation is pr... | 9805018v1 |
1998-11-04 | Cascades of energy and helicity in the GOY shell model of turbulence | The effect of extreme hyperviscous damping, $\nu k_n^p, p=\infty$ is studied
numerically in the GOY shell model of turbulence. It has resently been
demonstrated [Leveque and She, Phys. Rev. Lett, 75,2690 (1995)] that the
inertial range scaling in the GOY model is non-universal and depending on the
viscous damping. The ... | 9811009v1 |
1994-02-04 | Effects of Disorder in a Dilute Bose Gas | We discuss the effects of a weak random external potential on the properties
of the dilute Bose gas at zero temperature. The results recently obtained by
Huang and Meng for the depletion of the condensate and of the superfluid
density are recovered. Results for the shift of the velocity of sound as well
as for its damp... | 9402015v1 |
1995-02-10 | The influence of structure disorder on mean atomic momentum fluctuations and a spin-wave spectrum | The relation between atomic momenta fluctuations and density fluctuations is
obtained in frames of mean-field approximation. Using two-time temperature
Green functions within Tyablikov approximation the equations for spin
excitation energy and damping are obtained. The asymptotics of energy and
damping in the long-wave... | 9502042v1 |
1997-02-13 | Comment on "Collective Excitations of a Bose-Einstein Condensate in a Magnetic Trap" | We calculate the damping rate of collective excitations for a nearly pure
Bose-Einstein condensate regarding the recent experiments in MIT [M.-O. Mews et
al, Phys. Rev. Lett. 77, 988 (1996)]. The decay time of collective excitations
obtained in our theoretical calculations agrees well with their experimental
result. We... | 9702122v1 |
1997-08-14 | Landau damping in dilute Bose gases | Landau damping in weakly interacting Bose gases is investigated by means of
perturbation theory. Our approach points out the crucial role played by
Bose-Einstein condensation and yields an explicit expression for the decay rate
of elementary excitations in both uniform and non uniform gases. Systematic
results are deri... | 9708104v1 |
1997-11-07 | Coulomb suppression of NMR coherence peak in fullerene superconductors | The suppressed NMR coherence peak in the fullerene superconductors is
explained in terms of the dampings in the superconducting state induced by the
Coulomb interaction between conduction electrons. The Coulomb interaction,
modelled in terms of the onsite Hubbard repulsion, is incorporated into the
Eliashberg theory of... | 9711060v2 |
1997-12-09 | The Sound of Sonoluminescence | We consider an air bubble in water under conditions of single bubble
sonoluminescence (SBSL) and evaluate the emitted sound field nonperturbatively
for subsonic gas-liquid interface motion. Sound emission being the dominant
damping mechanism, we also implement the nonperturbative sound damping in the
Rayleigh-Plesset e... | 9712097v1 |
1998-07-02 | Linear systems with adiabatic fluctuations | We consider a dynamical system subjected to weak but adiabatically slow
fluctuations of external origin. Based on the ``adiabatic following''
approximation we carry out an expansion in \alpha/|\mu|, where \alpha is the
strength of fluctuations and 1/|\mu| refers to the time scale of evolution of
the unperturbed system ... | 9807031v1 |
1998-12-02 | Vortex lattice melting and the damping of the dHvA oscillations in the mixed state | Phase fluctuations in the superconducting order parameter, which are
responsible for the melting of the Abrikosov vortex lattice below the mean
field $H_{c2}$, are shown to dramatically enhance the scattering of
quasi-particles by the fluctuating pair potential, thus leading to enhanced
damping of the dHvA oscillations... | 9812040v1 |
1999-01-19 | Damping of Growth Oscillations | Computer simulations and scaling theory are used to investigate the damping
of oscillations during epitaxial growth on high-symmetry surfaces. The
crossover from smooth to rough growth takes place after the deposition of
(D/F)^\delta monolayers, where D and F are the surface diffusion constant and
the deposition rate, ... | 9901178v1 |
1999-06-15 | Temperature-induced resonances and Landau damping of collective modes in Bose-Einstein condensed gases in spherical traps | Interaction between collective monopole oscillations of a trapped
Bose-Einstein condensate and thermal excitations is investigated by means of
perturbation theory. We assume spherical symmetry to calculate the matrix
elements by solving the linearized Gross-Pitaevskii equations. We use them to
study the resonances of t... | 9906214v1 |
1999-08-03 | Kinetic Theory of Collective Modes in Atomic Clouds above the Bose-Einstein Transition Temperature | We calculate frequencies and damping rates of the lowest collective modes of
a dilute Bose gas confined in an anisotropic trapping potential above the
Bose-Einstein transition temperature. From the Boltzmann equation with a
simplified collision integral we derive a general dispersion relation that
interpolates between ... | 9908043v1 |
1999-09-01 | Normal Fermi Liquid Behavior of Quasiholes in the Spin-Polaron Model for Copper Oxides | Based on the t-J model and the self-consistent Born approximation, the
damping of quasiparticle hole states near the Fermi surface is calculated in a
low doping regime. Renormalization of spin-wave excitations due to hole doping
is taken into account. The damping is shown to be described by a familiar form
$\text{Im}\S... | 9909020v1 |
1999-12-01 | Impurity relaxation mechanism for dynamic magnetization reversal in a single domain grain | The interaction of coherent magnetization rotation with a system of two-level
impurities is studied. Two different, but not contradictory mechanisms, the
`slow-relaxing ion' and the `fast-relaxing ion' are utilized to derive a system
of integro-differential equations for the magnetization. In the case that the
impurity... | 9912014v1 |
2000-02-16 | Dissipative dynamics of Bose condensates in optical cavities | We study the zero temperature dynamics of Bose-Einstein condensates in driven
high-quality optical cavities in the limit of large atom-field detuning. We
calculate the stationary ground state and the spectrum of coupled atom and
field mode excitations for standing wave cavities as well as for travelling
wave cavities. ... | 0002247v1 |
2000-03-27 | Effect of memory and dynamical chaos in long Josephson junctions | A long Josephson junction in a constant external magnetic field and in the
presence of a dc bias current is investigated. It is shown that the system,
simulated by the sine-Gorgon equation, "remembers" a rapidly damping initial
perturbation and final asymptotic states are determined exactly with this
perturbation. Nume... | 0003421v1 |
2000-09-13 | Oscillations of the superconducting order parameter in a ferromagnet | Planar tunneling spectroscopy reveals damped oscillations of the
superconducting order parameter induced into a ferromagnetic thin film by the
proximity effect. The oscillations are due to the finite momentum transfer
provided to Cooper pairs by the splitting of the spin up and down bands in the
ferromagnet. As a conse... | 0009192v1 |
2000-09-29 | Damping and revivals of collective oscillations in a finite-temperature model of trapped Bose-Einstein condensation | We utilize a two-gas model to simulate collective oscillations of a
Bose-Einstein condensate at finite temperatures. The condensate is described
using a generalized Gross-Pitaevskii equation, which is coupled to a thermal
cloud modelled by a Monte Carlo algorithm. This allows us to include the
collective dynamics of bo... | 0009468v1 |
2001-04-18 | Effective rate equations for the over-damped motion in fluctuating potentials | We discuss physical and mathematical aspects of the over-damped motion of a
Brownian particle in fluctuating potentials. It is shown that such a system can
be described quantitatively by fluctuating rates if the potential fluctuations
are slow compared to relaxation within the minima of the potential, and if the
positi... | 0104330v1 |
2001-09-05 | Spin Excitations in a Fermi Gas of Atoms | We have experimentally investigated a spin excitation in a quantum degenerate
Fermi gas of atoms. In the hydrodynamic regime the damping time of the
collective excitation is used to probe the quantum behavior of the gas. At
temperatures below the Fermi temperature we measure up to a factor of 2
reduction in the excitat... | 0109098v2 |
2001-10-09 | Freezing of a Stripe Liquid | The existence of a stripe-liquid phase in a layered nickelate,
La(1.725)Sr(0.275)NiO(4), is demonstrated through neutron scattering
measurements. We show that incommensurate magnetic fluctuations evolve
continuously through the charge-ordering temperature, although an abrupt
decrease in the effective damping energy is ... | 0110191v2 |
2001-12-13 | Magnon softening and damping in the ferromagnetic manganites due to orbital correlations | We present a theory for spin excitations in ferromagnetic metallic manganites
and demonstrate that orbital fluctuations have strong effects on the magnon
dynamics in the case these compounds are close to a transition to an orbital
ordered state. In particular we show that the scattering of the spin
excitations by low-l... | 0112252v2 |
2002-01-16 | Quantum Spin dynamics of the Bilayer Ferromagnet La(1.2)Sr(1.8)Mn2O7 | We construct a theory of spin wave excitations in the bilayer manganite
La(1.2)Sr(1.8)Mn2O7 based on the simplest possible double-exchange model, but
including leading quantum corrections to the spin wave dispersion and damping.
Comparison is made with recent inelastic neutron scattering experiments. We
find that quant... | 0201269v1 |
2002-02-21 | Dynamics of a Bose-Einstein condensate at finite temperature in an atomoptical coherence filter | The macroscopic coherent tunneling through the barriers of a periodic
potential is used as an atomoptical filter to separate the condensate and the
thermal components of a $^{87}$Rb mixed cloud. We condense in the combined
potential of a laser standing-wave superimposed on the axis of a cigar-shape
magnetic trap and in... | 0202369v1 |
2002-03-11 | A Damping of the de Haas-van Alphen Oscillations in the superconducting state | Deploying a recently developed semiclassical theory of quasiparticles in the
superconducting state we study the de Haas-van Alphen effect. We find that the
oscillations have the same frequency as in the normal state but their amplitude
is reduced. We find an analytic formulae for this damping which is due to
tunnelling... | 0203224v1 |
2002-03-26 | Measurement induced quantum-classical transition | A model of an electrical point contact coupled to a mechanical system
(oscillator) is studied to simulate the dephasing effect of measurement on a
quantum system. The problem is solved at zero temperature under conditions of
strong non-equilibrium in the measurement apparatus. For linear coupling
between the oscillator... | 0203521v3 |
2002-07-04 | Fluctuations and correlations in hexagonal optical patterns | We analyze the influence of noise in transverse hexagonal patterns in
nonlinear Kerr cavities. The near field fluctuations are determined by the
neutrally stable Goldstone modes associated to translational invariance and by
the weakly damped soft modes. However these modes do not contribute to the far
field intensity f... | 0207127v2 |
2002-09-19 | Damping of long-wavelength collective excitations in quasi-onedimensional Fermi liquids | The imaginary part of the exchange-correlation kernel in the longitudinal
current-current response function of a quasi-onedimensional Fermi liquid is
evaluated by an approximate decoupling in the equation of motion for the
current density, which accounts for processes of excitation of two
particle-hole pairs. The two-p... | 0209455v1 |
2002-11-05 | Magnetic fluctuations and resonant peak in cuprates: a microscopic theory | The theory for the dynamical spin susceptibility within the t-J model is
developed, as relevant for the resonant magnetic peak and normal-state magnetic
response in superconducting (SC) cuprates. The analysis is based on the
equations of motion for spins and the memory-function presentation of magnetic
response where t... | 0211090v1 |
2002-11-20 | Damping of Nodal Fermions Caused by a Dissipative Mode | Using a $d_{x^2 - y^2}$ superconductor in 2+1 dimensions we show that the
Nambu Goldstone fluctuations are replaced by dissipative excitations. We find
that the nodal quasi-particles damping is caused by the strong dissipative
excitations near the nodal points. As a result we find that the scattering
rates are linear i... | 0211440v1 |
2003-05-27 | Dynamics of a classical gas including dissipative and mean field effects | By means of a scaling ansatz, we investigate an approximated solution of the
Boltzmann-Vlasov equation for a classical gas. Within this framework, we derive
the frequencies and the damping of the collective oscillations of a
harmonically trapped gas and we investigate its expansion after release of the
trap. The method... | 0305624v1 |
2003-07-21 | Chaotic scattering of a quantum particle weakly coupled to a very complicated background | Effect of a complicated many-body environment is analyzed on the chaotic
motion of a quantum particle in a mesoscopic ballistic structure. The dephasing
and absorption phenomena are treated on the same footing in the framework of a
model which is free of the ambiguities inherent to earlier models. The
single-particle d... | 0307496v1 |
2003-09-24 | Landau Damping in a 2D Electron Gas with Imposed Quantum Grid | Dielectric properties of semiconductor substrate with imposed two dimensional
(2D) periodic grid of quantum wires or nanotubes (quantum crossbars, QCB) are
studied. It is shown that a capacitive contact between QCB and semiconductor
substrate does not destroy the Luttinger liquid character of the long wave QCB
excitati... | 0309546v2 |
2003-11-21 | Self-stabilised fractality of sea-coasts through damped erosion | Erosion of rocky coasts spontaneously creates irregular seashores. But the
geometrical irregularity, in turn, damps the sea-waves, decreasing the average
wave amplitude. There may then exist a mutual self-stabilisation of the waves
amplitude together with the irregular morphology of the coast. A simple model
of such st... | 0311509v1 |
2003-12-10 | Exciton-LO-phonon dynamics in InAs/GaAs quantum dots: Effects of zone-edge phonon damping | The dynamics of an exciton-LO-phonon system after an ultrafast optical
excitation in an InAs/GaAs quantum dot is studied theoretically. Influence of
anharmonic phonon damping and its interplay with the phonon dispersion is
analyzed. The signatures of the zone-edge decay process in the absorption
spectrum and time evolu... | 0312256v2 |
2004-01-13 | Vortex waves and the onset of turbulence in $^3$He-B | In a recent experiment Finne et al. discovered an intrinsic condition for the
onset of quantum turbulence in $^3$He-B, that q=alpha/(1-alpha')<1, where alpha
and alpha' are mutual friction parameters. The authors argued that this
condition corresponds to Kelvin waves which are marginally damped, so for q>1
Kelvin waves... | 0401212v1 |
2004-01-28 | Long lived acoustic vibrational modes of an embedded nanoparticle | Classical continuum elastic calculations show that the acoustic vibrational
modes of an embedded nanoparticle can be lightly damped even when the
longitudinal plane wave acoustic impedances $Z_o=\rho v_L$ of the nanoparticle
and the matrix are the same. It is not necessary for the matrix to be less
dense or softer than... | 0401579v2 |
2004-07-20 | Dynamics of a trapped ultracold two-dimensional atomic gas | This article is devoted to the study of two-dimensional Bose gases
harmonically confined. We first summarize their equilibrium properties. For
such a gas above the critical temperature, we also derive the frequencies and
the damping of the collective oscillations and we investigate its expansion
after releasing of the ... | 0407522v1 |
2004-12-06 | Thermal wave packets induced by attosecond laser pulses | In this paper the dynamics of the interaction of attosecond laser pulses with
matter is investigated. It will be shown that the master equation: modified
Klein-Gordon equation describes the propagation of the heatons. Heatons are the
thermal wave packets. When the duration of the laser pulsees \delta t is of the
order ... | 0412126v1 |
2005-04-12 | Nonlinear response and discrete breather excitation in driven micro-mechanical cantilever arrays | We explain the origin of the generation of discrete breathers (DBs) in
experiments on damped and driven micromechanical cantilever arrays (M.Sato et
al. Phys. Rev. Lett. {\bf 90}, 044102, 2003). Using the concept of the
nonlinear response manifold (NLRM) we provide a systematic way to find the
optimal parameter regime ... | 0504298v1 |
2005-05-14 | Monopole Oscillations and Dampings in Boson and Fermion Mixture in the Time-Dependent Gross-Pitaevskii and Vlasov Equations | We construct a dynamical model for the time evolution of the boson-fermion
coexistence system. The dynamics of bosons and fermions are formulated with the
time-dependent Gross-Pitaevsky equation and the Vlasov equation. We thus study
the monopole oscillation in the bose-fermi mixture. We find that large damping
exists ... | 0505357v1 |
2005-10-13 | Superconducting Flywheel Model for Energy Storage Applications | In order to explore the complexity and diversity of the flywheels' dynamics,
we have developed the real-physics computer model of a universal mechanical
rotor. Due to an arbitrary external force concept, the model can be adjusted to
operate identical to the real experimental prototype. Taking the high-speed
magnetic ro... | 0510346v1 |
2005-11-05 | Ratchet Effect in Magnetization Reversal of Stoner Particles | A new strategy is proposed aimed at substantially reducing the minimal
magnetization switching field for a Stoner particle. Unlike the normal method
of applying a static magnetic field which must be larger than the magnetic
anisotropy, a much weaker field, proportional to the damping constant in the
weak damping regime... | 0511135v1 |
2005-12-03 | Apparent vibrational side-bands in pi-conjugated systems: the case of distyrylbenzene | The photoluminescence (PL) spectra of dilute solution and single crystals of
distyrylbenzene show unique temperature dependent vibronic structures. The
characteristic single frequency progression at high temperatures is modulated
by a low frequency progression series at low temperatures. None of the series
side band mo... | 0512067v1 |
2006-05-26 | Thermo-Plasma Polariton within Scaling Theory of Single-Layer Graphene | Electrodynamics of single-layer graphene is studied in the scaling regime. At
any finite temperature, there is a weakly damped collective thermo-plasma
polariton mode whose dispersion and wavelength dependent damping is determined
analytically. The electric and magnetic fields associated with this mode decay
exponentia... | 0605642v1 |
2006-12-18 | Shear viscosity and damping for a Fermi gas in the unitarity limit | The shear viscosity of a two-component Fermi gas in the normal phase is
calculated as a function of temperature in the unitarity limit, taking into
account strong-coupling effects that give rise to a pseudogap in the spectral
density for single-particle excitations. The results indicate that recent
measurements of the ... | 0612460v2 |
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