cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Enhanced Magnetism in Heterostructures with Transition-Metal Dichalcogenide Monolayers
Creators: name: Dang, Diem Thi-Xuan
name: Barik, Ranjan Kumar
name: Phan, Manh-Huong
name: Woods, Lilia M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Two-dimensional materials and their heterostructures have opened up new possibilities for magnetism at the nanoscale. In this study, we utilize first-principles simulations to investigate the structural, electronic, and magnetic properties of $\textrm{Fe}/\textrm{WSe}_2/\textrm{Pt}$ systems containing pristine, defective, or doped $\textrm{WSe}_2$ monolayers. The proximity effects of the ferromagnetic Fe layer are studied by considering defective and vanadium-doped $\textrm{WSe}_2$ monolayers. All heterostructures are found to be ferromagnetic, and the insertion of the transition-metal dichalcogenide results in a redistribution of spin orientation and an increased density of magnetic atoms due to the magnetized $\textrm{WSe}_2$. There is an increase in the overall total density of states at the Fermi level due to $\textrm{WSe}_2$; however, the transition-metal dichalcogenide may lose its distinct semiconducting properties due to the stronger than van der Waals coupling. Spin-resolved electronic structure properties are linked to larger spin Seebeck coefficients found in heterostructures with $\textrm{WSe}_2$ monolayers.
description: 22 pages, 5 figures, 1 table
Analytical theory of modulated magnetic solitons
Creators: name: Bookman, Lake
name: Hoefer, Mark
Publisher: name: arXiv
Year: 2013
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Droplet solitons are coherently precessing solitary waves that have been recently realized in thin ferromagnets with perpendicular anisotropy.In the strongly nonlinear regime, droplets can be well approximated by a slowly precessing, circular domain wall with a hyperbolic tangent form. Utilizing this representation, this work develops a general droplet modulation theory and applies it to study the long range effects of the magnetostatic field and a nanocontact spin torque oscillator (NC-STO) where spin polarized currents act as a gain source to counteract magnetic damping. An analysis of the dynamical equations for the droplet's center, frequency and phase demonstrates a negative processional frequency shift due to long range dipolar interactions, dependent on film thickness. Further analysis also demonstrates the onset of a saddle-node bifurcation at the minimum sustaining current for the NC-STO. The basin of attraction associated with the stable node demonstrates that spin torque enacts a restoring force to excursions of the droplet from the nanocontact center, observed previously in numerical simulations. Large excursions lead to the droplet's eventual decay into spin waves.
Scattering lengths in isotopologues of the RbYb system
Creators: name: Borkowski, Mateusz
name: Żuchowski, Piotr S.
name: Ciuryło, Roman
name: Julienne, Paul S.
name: Kędziera, Dariusz
name: Mentel, Łukasz
name: Tecmer, Paweł
name: Münchow, Frank
name: Bruni, Christian
name: Görlitz, Axel
Publisher: name: arXiv
Year: 2013
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We model the binding energies of rovibrational levels of the RbYb molecule using experimental data from two-color photoassociation spectroscopy in mixtures of ultracold $^{87}$Rb with various Yb isotopes. The model uses a theoretical potential based on state-of-the-art \emph{ab initio} potentials, further improved by least-squares fitting to the experimental data. We have fixed the number of bound states supported by the potential curve, so that the model is mass scaled, that is, it accurately describes the bound state energies for all measured isotopic combinations. Such a model enables an accurate prediction of the s-wave scattering lengths of all isotopic combinations of the RbYb system. The reduced mass range is broad enough to cover the full scattering lengths range from $-\infty$ to $+\infty$. For example, the $^{87}$Rb$^{174}$Yb system is characterized by a large positive scattering length of $+880(120)$~a.u., while $^{87}$Rb$^{173}$Yb has $a=-626(88)$~a.u.. On the other hand $^{87}$Rb$^{170}$Yb has a very small scattering length of $-14.5(1.8)$~a.u. confirmed by the pair's extremely low thermalization rate. For isotopic combinations including $^{85}$Rb the variation of the interspecies scattering lengths is much smoother ranging from $+39.0(1.6)$ a.u. for $^{85}$Rb$^{176}$Yb to $+230(10)$ a.u. in the case of $^{85}$Rb$^{168}$Yb. Hyperfine corrections to these scattering lengths are also given. We further complement the fitted potential with interaction parameters calculated from alternative methods. The recommended value of the van der Waals coefficient is $C_6$=2837(13)~a.u. and is in agreement and more precise than the current state-of-the-art theoretical predictions (S. G. Porsev, M. S. Safronova, A. Derevianko, and C.W. Clark, arXiv:1307.2654 (2013)).
description: 12 pages, 4 figures
Wache. Halt! wer da? Herr Samuel Muffeles: Wai geschrien! haben Sie mich doch erschreckt. Wache. Wer da? H.S.M. Samuel Muffeles, Emancipirter Handelsmann der Stadt No. 1738 2te Stiege 3ten Stock wenn Sie vielleicht eppes e Geschäft machen wollen in Pottasche. Wache. Sagen Sie: gut Freund! H.S.M. o infim! war mir ein besonderes Vergnügen!; [1848]
Creators: name: (:Unav)
Publisher: name: Universitätsbibliothek der Ludwig-Maximilians-Universität München
Year: 2018

description: Zählung: VII / 6
Mean range bunching of exotic nuclei produced by in-flight fragmentation and fission -- Stopped-beam experiments with increased efficiency
Creators: name: Dickel, Timo
name: Hornung, Christine
name: Amanbayev, Daler
name: Andres, Samuel Ayet San
name: Beck, Soenke
name: Bergmann, Julian
name: Geissel, Hans
name: Gerl, Juergen
name: Gorska, Magdalena
name: Groef, Lizzy
name: Haettner, Emma
name: Hucka, Jan-Paul
name: Kostyleva, Daria A.
name: Kripko-Koncz, Gabriella
name: Mollaebrahimi, Ali
name: Mukha, Ivan
name: Pietri, Stephane
name: Plaß, Wolfgang R.
name: Podolyak, Zsolt
name: Purushothaman, Sivaji
name: Reiter, Moritz Pascal
name: Roesch, Heidi
name: Scheidenberger, Christoph
name: Tanaka, Yoshiki K.
name: Weick, Helmut
name: Zhao, Jianwei
name: Collaboration, Super-FRS Experiment
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The novel technique of mean range bunching has been developed and applied at the projectile fragment separator FRS at GSI in four experiments of the FAIR phase-0 experimental program. Using a variable degrader system at the final focal plane of the FRS, the ranges of the different nuclides can be aligned, allowing to efficiently implant a large number of different nuclides simultaneously in a gas-filled stopping cell or an implantation detector. Stopping and studying a cocktail beam overcomes the present limitations of stopped-beam experiments. The conceptual idea of mean range bunching is described and illustrated using simulations. In a single setting of the FRS, 37 different nuclides were stopped in the cryogenic stopping cell and were measured in a single setting broadband mass measurement with the multiple-reflection time-of-flight mass spectrometer of the FRS Ion Catcher.
A Spin Field Effect Transistor Based on a Strained Two Dimensional Layer of a Weyl Semimetal
Creators: name: Rahman, Rahnuma
name: Bandyopadhyay, Supriyo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Spin field effect transistors (SpinFET) are an iconic class of spintronic devices that exploit gate tuned spin-orbit interaction in semiconductor channels interposed between ferromagnetic source and drain contacts to elicit transistor functionality. Recently, a new type of SpinFET based on gate tuned strain in quantum materials (e.g. topological insulators) has been proposed and may have interesting analog applications, such as in frequency multiplication, by virtue of its unusual oscillatory transfer characteristic. Here, we propose and analyze yet another type of SpinFET in this class, which may have a different application. It is based on a Weyl semimetal. Because the operating principle is non-classical, the channel conductance shows oscillatory dependence on the channel length at zero gate voltage. Furthermore, the transconductance can switch sign if the channel length is varied. This latter feature can be exploited to implement a complementary device like CMOS by connecting two such SpinFETs of slightly different channel lengths in series. These unusual properties may have niche applications.
Remote sensor response study in the regime of the microwave radiation-induced magnetoresistance oscillations
Creators: name: Ye, Tianyu
name: Mani, Ramesh
name: Wegscheider, Werner
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A concurrent remote sensing and magneto-transport study of the microwave excited two dimensional electron system (2DES) at liquid Helium temperatures has been carried out using a carbon detector to remotely sense the microwave activity of the 2D electron system in the GaAs/AlGaAs heterostructure during conventional magnetotransport measurements. Various correlations are observed and reported between the oscillatory magnetotransport and the remotely sensed reflection. In addition, the oscillatory remotely sensed signal is shown to exhibit a power law type variation in its amplitude, similar to the radiation-induced magnetoresistance oscillations.
On the solution to the NLO forward BFKL equation
Creators: name: Grabovsky, A. V.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: It is demonstrated that the NLO forward BFKL equation can be solved in the space of its Born eigenfunctions.
description: 6 pages
A Preliminary Calibration of the RR Lyrae Period-Luminosity Relation at Mid-Infrared Wavelengths: WISE Data
Creators: name: Madore, Barry F.
name: Hoffman, Douglas
name: Freedman, Wendy L.
name: Kollmeier, Juna A.
name: Monson, Andy
name: Persson, S. Eric
name: Rich, Jeff A.
name: Scowcroft, Victoria
name: Seibert, Mark
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Using time-resolved, mid-infrared data from WISE and geometric parallaxes from HST for four Galactic RR Lyrae variables, we derive the following Population II Period-Luminosity (PL) relations for the WISE [W1], [W2] and [W3] bands at 3.4, 4.6 & 12 um, respectively: M[W1] = -2.44 (+/- 0.95) x logP - 1.26 (+/- 0.25) sigma = 0.10 M[W2] = -2.55 (+/- 0.89) x logP - 1.29 (+/- 0.23) sigma = 0.10 M[W3] = -2.58 (+/- 0.97) x logP - 1.32 (+/- 0.25) sigma = 0.10 The slopes and the scatter around the fits are consistent with a smooth extrapolation of those same quantities from previously-published K-band observations at 2.2 um, where the asymptotic (long-wavelength) behavior is consistent with a Period-Radius relation having a slope of 0.5. No obvious correlation with metallicity (spanning 0.4 dex in [Fe/H]) is found in the residuals of the four calibrating RR Lyrae stars about the mean PL regression line.
description: 10 pages, 5 figures, 6 data tables. Accepted to the Astrophysical Journal
Edge spin accumulation in 2D electron and hole systems in a quasi-ballistic regime
Creators: name: Khaetskii, Alexander
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider a two-dimensional structure with spin-orbit-related splitting of the electron (hole) spectrum and calculate the edge spin density which appears due to the intrinsic mechanism of spin-orbit interaction in the presence of a charge current through the structure. We concentrate on the quasi-ballistic case when a mean free path, being much smaller than the sample size, is larger than the spin precession length determined by the value of the spin-orbit splitting. We show that regardless of the presence or absence of the bulk spin current the main source of the edge spin density is the boundary scattering itself. The character of the edge spin density depends on the smoothness of the bulk impurity potential. We have calculated the edge spin density profile for an arbitrary smoothness of the scattering potential in the bulk, and discussed relation to the existing experiments for two-dimensional holes.
description: 6 pages, 1 fig
Phase-change radiative thermal diode
Creators: name: Ben-Abdallah, Philippe
name: Biehs, Svend-Age
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A thermal diode transports heat mainly in one preferential direction rather than in the opposite direction. This behavior is generally due to the non-linear dependence of certain physical properties with respect to the temperature. Here we introduce a radiative thermal diode which rectifies heat transport thanks to the phase transitions of materials. Rectification coefficients greater than 70% and up to 90% are shown, even for small temperature differences. This result could have important applications in the development of futur contactless thermal circuits or in the conception of radiative coatings for thermal management.
Model independent X-ray standing wave analysis of periodic multilayer structures
Creators: name: Yakunin, S. N.
name: Makhotkin, I. A.
name: Chuev, M. A.
name: Pashaev, E. M.
name: Zoethout, E.
name: Louis, E.
name: van de Kruijs, R. W. E.
name: Seregin, S. Yu.
name: Subbotin, I. A.
name: Novikov, D. V.
name: Bijkerk, F.
name: Kovalchuk, M. V.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We present a model independent approach for the reconstruction of the atomic concentration profile in a nanoscale layered structure, as measured using the X-ray fluorescence yield modulated by an X-ray standing wave (XSW). The approach is based on the direct regularized solution of the system of linear equations that characterizes the fluorescence yield. The suggested technique was optimized for, but not limited to, the analysis of periodic layered structures where the XSW is formed under Bragg conditions. The developed approach was applied to the reconstruction of the atomic concentration profiles for LaN/BN multilayers with 50 periods of 35 A thick layers. The object is especially difficult to analyse with traditional methods, as the estimated thickness of the interface region between the constituent materials is comparable to the individual layer thicknesses. However, using the suggested technique it was possible to reconstruct the La atomic profile, showing that the La atoms stay localized within the LaN layers and interfaces and do not diffuse into the BN layer. The atomic distributions were found with an accuracy of 1 A. The analysis of the Kr fluorescence yield showed that Kr atoms originating from the sputter gas are trapped in both the LaN-on-BN and the BN-on-LaN interfaces.
description: 10 pages, 6 figures. The article presents the latest findings on the application of X-ray Standing Waves (XSW) technique for the analysis of periodic multilayer structures. A novel approach of the data treatment for XSW was proposed. The efficiency of developed approached was illustrated by the analysis of the atomic profiles in LaN/B4C multilayer mirror with a period thickness of 4.3 nm
SR-GAN for SR-gamma: super resolution of photon calorimeter images at collider experiments
Creators: name: Erdmann, Johannes
name: van der Graaf, Aaron
name: Mausolf, Florian
name: Nackenhorst, Olaf
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We study single-image super-resolution algorithms for photons at collider experiments based on generative adversarial networks. We treat the energy depositions of simulated electromagnetic showers of photons and neutral-pion decays in a toy electromagnetic calorimeter as 2D images and we train super-resolution networks to generate images with an artificially increased resolution by a factor of four in each dimension. The generated images are able to reproduce features of the electromagnetic showers that are not obvious from the images at nominal resolution. Using the artificially-enhanced images for the reconstruction of shower-shape variables and of the position of the shower center results in significant improvements. We additionally investigate the utilization of the generated images as a pre-processing step for deep-learning photon-identification algorithms and observe improvements in the case of training samples of small size.
description: 26 pages, 13 figures
Search for Rare Nuclear Decays with HPGe Detectors at the STELLA Facility of the LNGS
Creators: name: Belli, P.
name: Bernabei, R.
name: Cappella, F.
name: Cerulli, R.
name: Danevich, F. A.
name: d'Angelo, A.
name: d'Angelo, S.
name: Di Marco, A.
name: Di Vacri, M. L.
name: Incicchitti, A.
name: Kobychev, V. V.
name: Kovtun, G. P.
name: Kovtun, N. G.
name: Laubenstein, M.
name: Nisi, S.
name: Poda, D. V.
name: Polischuk, O. G.
name: Shcherban, A. P.
name: Solopikhin, D. A.
name: Suhonen, J.
name: Tolmachev, A. V.
name: Tretyak, V. I.
name: Yavetskiy, R. P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Results on the search for rare nuclear decays with the ultra low background facility STELLA at the LNGS using gamma ray spectrometry are presented. In particular, the best T1/2 limits were obtained for double beta processes in 96Ru and 104Ru. Several isotopes, which potentially decay through different double beta decay channels, including also possible resonant double electron captures, were investigated for the first time (156Dy, 158Dy, 184Os, 192Os, 190Pt, 198Pt). Search for resonant absorption of solar 7Li axions in a LiF crystal gave the best limit for the mass of 7Li axions (< 8.6 keV). Rare alpha decay of 190Pt to the first excited level of 186Os (Eexc = 137.2 keV) was observed for the first time.
description: 4 pages, contribution to the MEDEX'13 Conference, corrected list of authors
An Eigenvalue-Free Implementation of the Log-Conformation Formulation
Creators: name: Becker, Florian
name: Rauthmann, Katharina
name: Pauli, Lutz
name: Knechtges, Philipp
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Numerical Analysis (math.NA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: The log-conformation formulation, although highly successful, was from the beginning formulated as a partial differential equation that contains an, for PDEs unusual, eigenvalue decomposition of the unknown field. To this day, most numerical implementations have been based on this or a similar eigenvalue decomposition, with Knechtges et al. (2014) being the only notable exception for two-dimensional flows. In this paper, we present an eigenvalue-free algorithm to compute the constitutive equation of the log-conformation formulation that works for two- and three-dimensional flows. Therefore, we first prove that the challenging terms in the constitutive equations are representable as a matrix function of a slightly modified matrix of the log-conformation field. We give a proof of equivalence of this term to the more common log-conformation formulations. Based on this formulation, we develop an eigenvalue-free algorithm to evaluate this matrix function. The resulting full formulation is first discretized using a finite volume method, and then tested on the confined cylinder and sedimenting sphere benchmarks.
description: 23 pages, 6 figures, 6 tables
Physics Teaching and Educational Interdisciplinarity with A.V. Usova Revisited
Creators: name: Yavoruk, Oleg
Publisher: name: arXiv
Year: 2022
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: The paper deals with pedagogical heritage of A.V. Usova (1921-2014) that yields insights into problems of interdisciplinary relationship in the school science education system. Her fundamental works were used as teaching guides in the preparation of physics teachers of all pedagogical universities of the Soviet Union and Russia. In this study, professor Usova is not an interdisciplinary researcher; she is a researcher of interdisciplinarity. Here is provided a short and consistent description of her views on teaching physics as a foundation of educational interdisciplinarity. Usova elaborated educational functions, classifications, organizational levels, ways of instantiating, content-related foundations of interdisciplinary relations, recommendations for practical applying interdisciplinary relations. Besides, Usova suggested a unified approach to the study of knowledge and skills through the generalized plans. And we would like not simply clarify, retell or restate the very powerful didactic discoveries of Usova, but consider opportunities of teaching across boundaries for actual educational challenges. The future of the field of didactics, which deals with the study of interdisciplinarity, is very interesting and attractive. This problem will always excite scientists, educators and teachers, and the futurity of science education depends on the ways it is solved.
description: 8 pages
Cooperative Short Range Routing for Energy Savings in Multi-Interface Wireless Networks
Creators: name: Fedrizzi, Riccardo
name: Rasheed, Tinku
Publisher: name: arXiv
Year: 2013
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: Energy efficiency in wireless networks has become an important field of research due to ever increasing energy expenditure in battery supplied mobile terminals. In this paper we present an energy efficient routing scheme for multi-standard infrastructure wireless networks based on multi-hop cooperative relaying. The aim of the proposed technique is to exploit short-range cooperation to take benefit from mobile terminals having superior links thus enable energy efficiency. Performance results show that higher data-rate yielded by cooperation can compensate the expense of higher energy due to multiple interfaces active on the same mobile terminal, making possible to observe energy efficiency gain of the system. A maximum achievable energy efficiency gain of up to 42 % was observed in our simulations when using the cooperative short range routing technique.
description: Accepted at IEEE VTC-Spring Conference 2013, Dresden, June 2013
Summations of large logarithms by parton showers
Creators: name: Nagy, Zoltan
name: Soper, Davison E.
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2020
Subjects: quantum chromodynamics: perturbation theory
parton: showers
resummation
perturbative QCD
parton shower

description: We propose a method to examine how a parton shower sums large logarithms. In this method, one works with an appropriate integral transform of the distribution for the observable of interest. Then, one reformulates the parton shower so as to obtain the transformed distribution as an exponential for which one can compute the terms in the perturbative expansion of the exponent.
Production of Strange, Non-strange particles and Hypernuclei in an Excluded-Volume Model
Creators: name: Tiwari, S. K.
name: Singh, C. P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a systematic study of production of strange and non-strange hadron yields and their ratios obtained in various experiments using our thermodynamically consistent excluded-volume model. We also analyze the production of light nuclei, hypernuclei and their antinuclei in terms of our excluded-volume model over a broad energy range starting from Alternating Gradient Synchrotron (AGS) to Large Hadron Collider (LHC) energies. Further, we extend our model for studying rapidity spectra of hadrons produced in heavy-ion collisions.
description: 4 pages, 5 figures, Invited talk in Strangeness in Quark Matter (SQM)-2013, Birmingham, U.K
Real double flag variety for the symmetric pair $(U(p,p),GL_{p}(\mathbb{C}))$ and Galois cohomology
Creators: name: Nishiyama, Kyo
name: Tauchi, Taito
Publisher: name: arXiv
Year: 2025
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: Primary 14M15, Secondary 05E14, 11E72, 22E46

description: Let $G$ be the indefinite unitary group $U(p,p)$, $H\simeq GL_{p}(\mathbb{C})$ its symmetric subgroup, $P_{S}$ the Siegel parabolic subgroup of $G$, and $B_{H}$ a Borel subgroup of $H$. In this article, we give a classification of the orbit decomposition $H\backslash (H/B_{H}\times G/P_{S})$ of the real double flag variety by using the Galois cohomology in the case where $p=2$.
description: 11 pages
Skyrmion motion in magnetic anisotropy gradients: Acceleration caused by deformation
Creators: name: de Assis, Ismael Ribeiro
name: Mertig, Ingrid
name: Göbel, Börge
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Magnetic skyrmions are nano-sized topologically non-trivial spin textures that can be moved by external stimuli such as spin currents and internal stimuli such as spatial gradients of a material parameter. Since the total energy of a skyrmion depends linearly on most of these parameters, like the perpendicular magnetic anisotropy, the exchange constant, or the Dzyaloshinskii-Moriya interaction strength, a skyrmion will move uniformly in a weak parameter gradient. In this paper, we show that the linear behavior changes once the gradients are strong enough so that the magnetic profile of a skyrmion is significantly altered throughout the propagation. In that case, the skyrmion experiences acceleration and moves along a curved trajectory. Furthermore, we show that when spin-orbit torques and material parameter gradients trigger a skyrmion motion, it can move on a straight path along the current or gradient direction. We discuss the significance of suppressing the skyrmion Hall effect for spintronic and neuromorphic applications of skyrmions. Lastly, we extend our discussion and compare it to a gradient generated by the Dzyaloshinskii-Moriya interaction.
description: Marie Sk{\l}odowska-Curie Actions, H2020-MSCA-ITN-2020; Project acronym SPEAR; Grant Agreement No. 955671
FastSurfer-HypVINN: Automated sub-segmentation of the hypothalamus and adjacent structures on high-resolutional brain MRI
Creators: name: Estrada, Santiago
name: Kügler, David
name: Bahrami, Emad
name: Xu, Peng
name: Mousa, Dilshad
name: Breteler, Monique M. B.
name: Aziz, N. Ahmad
name: Reuter, Martin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: The hypothalamus plays a crucial role in the regulation of a broad range of physiological, behavioural, and cognitive functions. However, despite its importance, only a few small-scale neuroimaging studies have investigated its substructures, likely due to the lack of fully automated segmentation tools to address scalability and reproducibility issues of manual segmentation. While the only previous attempt to automatically sub-segment the hypothalamus with a neural network showed promise for 1.0 mm isotropic T1-weighted (T1w) MRI, there is a need for an automated tool to sub-segment also high-resolutional (HiRes) MR scans, as they are becoming widely available, and include structural detail also from multi-modal MRI. We, therefore, introduce a novel, fast, and fully automated deep learning method named HypVINN for sub-segmentation of the hypothalamus and adjacent structures on 0.8 mm isotropic T1w and T2w brain MR images that is robust to missing modalities. We extensively validate our model with respect to segmentation accuracy, generalizability, in-session test-retest reliability, and sensitivity to replicate hypothalamic volume effects (e.g. sex-differences). The proposed method exhibits high segmentation performance both for standalone T1w images as well as for T1w/T2w image pairs. Even with the additional capability to accept flexible inputs, our model matches or exceeds the performance of state-of-the-art methods with fixed inputs. We, further, demonstrate the generalizability of our method in experiments with 1.0 mm MR scans from both the Rhineland Study and the UK Biobank. Finally, HypVINN can perform the segmentation in less than a minute (GPU) and will be available in the open source FastSurfer neuroimaging software suite, offering a validated, efficient, and scalable solution for evaluating imaging-derived phenotypes of the hypothalamus.
description: Accepted in Imaging Neuroscience
Microscopic description of nuclear vibrations: Relativistic QRPA and its extensions with quasiparticle-vibration coupling
Creators: name: Litvinova, Elena
name: Tselyaev, Victor
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The recent extensions of the covariant energy density functional theory with the quasiparticle-vibration coupling (QVC) are reviewed. Formulation of the Quasiparticle Random Phase Approximation (QRPA) in the relativistic framework is discussed. Self-consistent extensions of the relativistic QRPA imply the QVC which is implemented in two-body propagators in the nuclear medium. This provides fragmentation of the QRPA states describing the damping of the vibrational motion.
description: Published in "50 Years of Nuclear BCS", edited by R. A. Broglia and V.G. Zelevinsky, World Scientific (2013)
Fitting of interatomic potentials without forces: a parallel particle swarm optimization algorithm
Creators: name: González, Diego
name: Davis, Sergio
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present a methodology for fitting interatomic potentials to ab initio data, using the particle swarm optimization (PSO) algorithm, needing only a set of positions and energies as input. The prediction error of energies associated with the fitted parameters can be close to 1 meV/atom or lower, for reference energies having a standard deviation of about 0.5 eV/atom. We tested our method by fitting a Sutton-Chen potential for copper from \emph{ab initio} data, which is able to recover structural and dynamical properties, and obtain a better agreement of the predicted melting point versus the experimental value, as compared to the prediction of the standard Sutton-Chen parameters.
Learning to embed semantic similarity for joint image-text retrieval
Creators: name: Malali, Noam
name: Keller, Yosi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: We present a deep learning approach for learning the joint semantic embeddings of images and captions in a Euclidean space, such that the semantic similarity is approximated by the L2 distances in the embedding space. For that, we introduce a metric learning scheme that utilizes multitask learning to learn the embedding of identical semantic concepts using a center loss. By introducing a differentiable quantization scheme into the end-to-end trainable network, we derive a semantic embedding of semantically similar concepts in Euclidean space. We also propose a novel metric learning formulation using an adaptive margin hinge loss, that is refined during the training phase. The proposed scheme was applied to the MS-COCO, Flicke30K and Flickr8K datasets, and was shown to compare favorably with contemporary state-of-the-art approaches.
description: in IEEE Transactions on Pattern Analysis and Machine Intelligence, 2023
Interacting modified holographic Ricci dark energy model and statefinder diagnosis in flat universe
Creators: name: P, Praseetha
name: Mathew, Titus K
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this work we have considered the modified holographic Ricci dark energy interacting with dark matter through a non-gravitational coupling. We took three phenomenological forms for the interaction term $Q$ in the model, where in general $Q$ is proportional to the Hubble parameter and densities of the dark sectors, $ρ_{de}+ρ_m, \, ρ_m$ and $ρ_{de}$ respectively. We have obtained analytical solutions for the three interacting models, and studied the evolutions of equations of state parameter, deceleration parameter. The results are compared with the observationally constrained values for the best parameters of the model. We have also done the statefinder analysis of the model to discriminate the model from other standard models. In general we have shown that the model is showing a de Sitter type behavior in the far future of the evolution of the universe.
Nuclear magnetic resonance studies of pseudospin fluctuations in URu$_2$Si$_2$
Creators: name: Shirer, K. R.
name: Haraldsen, J. T.
name: Dioguardi, A. P.
name: Crocker, J.
name: apRoberts-Warren, N.
name: Shockley, A. C.
name: Lin, C. -H.
name: Nisson, D. M.
name: Cooley, J. C.
name: Janoschek, M.
name: Huang, K.
name: Kanchanavatee, N.
name: Maple, M. B.
name: Graf, M. J.
name: Balatsky, A. V.
name: Curro, N. J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report $^{29}$Si NMR measurements in single crystals and aligned powders of URu$_2$Si$_2$ in the hidden order and paramagnetic phases. The spin-lattice-relaxation data reveal evidence of pseudospin fluctuations of U moments in the paramagnetic phase. We find evidence for partial suppression of the density of states below 30 K, and analyze the data in terms of a two component spin-fermion model. We propose that this behavior is a realization of a pseudogap between the hidden order transition $T_{HO}$ and 30 K. This behavior is then compared to other materials that demonstrate precursor fluctuations in a pseudogap regime above a ground state with long-range order.
description: 5 pages, 3 figures
The effect of an external magnetic field on the determination of E1M1 two-photon decay rates in Be-like ions
Creators: name: Grumer, Jon
name: Li, Wenxian
name: Bernhardt, Dietrich
name: Li, Jiguang
name: Schippers, Stefan
name: Brage, Tomas
name: Jönsson, Per
name: Hutton, Roger
name: Zou, Yaming
Publisher: name: arXiv
Year: 2013
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: In this work we report on ab initio theoretical results for the magnetic field induced 2s2p ^3P_0 - 2s^2 ^1S_0 E1 transition for ions in the beryllium isoelectronic sequence between Z=5 and 92. It has been proposed that the rate of the E1M1 two-photon transition 2s2p ^3P_0 - 2s^2 ^1S_0 can be extracted from the lifetime of the ^3P_0 state in Be-like ions with zero nuclear spin by employing resonant recombination in a storage-ring. This experimental approach involves a perturbing external magnetic field. The effect of this field needs to be evaluated in order to properly extract the two-photon rate from the measured decay curves. The magnetic field induced transition rates are carefully evaluated and it is shown that, with a typical storage-ring field strength, it is dominant or of the same order as the E1M1 rate for low- and mid-Z ions. Results for several field strengths and ions are presented and we also give a simple Z-dependent formula for the rate. We estimate the uncertainties of our model to be within 5% for low- and mid-Z ions, and slightly larger for more highly charged ions. Furthermore we evaluate the importance of including both perturber states, ^3P_1 and ^1P_1, and it is shown that excluding the influence of the ^1P_1 perturber overestimates the rate by up to 26% for the mid-Z ions.
description: 21 pages, 5 figures
Webs and Posets
Creators: name: Dukes, Mark
name: Gardi, Einan
name: McAslan, Heather
name: Scott, Darren J.
name: White, Chris D.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The non-Abelian exponentiation theorem has recently been generalised to correlators of multiple Wilson line operators. The perturbative expansions of these correlators exponentiate in terms of sets of diagrams called webs, which together give rise to colour factors corresponding to connected graphs. The colour and kinematic degrees of freedom of individual diagrams in a web are entangled by mixing matrices of purely combinatorial origin. In this paper we relate the combinatorial study of these matrices to properties of partially ordered sets (posets), and hence obtain explicit solutions for certain families of web-mixing matrix, at arbitrary order in perturbation theory. We also provide a general expression for the rank of a general class of mixing matrices, which governs the number of independent colour factors arising from such webs. Finally, we use the poset language to examine a previously conjectured sum rule for the columns of web-mixing matrices which governs the cancellation of the leading subdivergences between diagrams in the web. Our results, when combined with parallel developments in the evaluation of kinematic integrals, offer new insights into the all-order structure of infrared singularities in non-Abelian gauge theories.
description: 42 pages, 21 figures
Imaging with a gravitational lens: the geometric view
Creators: name: Toth, Viktor T.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate imaging point sources with a monopole gravitational lens, such as the Solar Gravitational Lens in the geometric optics limit. We compute the light amplification of the lens used in conjunction with a telescope featuring a circular aperture that is placed in the focal region of the lens, compared to the amount of light collected by the same telescope unaided by a gravitational lens. We recover an averaged point-spread function that is in robust agreement with a wave-theoretical description of the lens, and can be used in practical calculations or simulations.
description: 6 pages, 6 figures, final submitted version after referee comments
Minimal area submanifolds in AdS x compact
Creators: name: Graham, C. Robin
name: Karch, Andreas
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We describe the asymptotic behavior of minimal area submanifolds in product spacetimes of an asymptotically hyperbolic space times a compact internal manifold. In particular, we find that unlike the case of a minimal area submanifold just in an asymptotically hyperbolic space, the internal part of the boundary submanifold is constrained to be itself a minimal area submanifold. For applications to holography, this tells us what are the allowed "flavor branes" that can be added to a holographic field theory. We also give a compact geometric expression for the spectrum of operator dimensions associated with the slipping modes of the submanifold in the internal space. We illustrate our results with several examples, including some that haven't appeared in the literature before.
description: 24 pages, no figures
Gravitational anomaly detection using a satellite constellation: Analysis and simulation
Creators: name: Toth, Viktor T.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate the utility of a constellation of four satellites in heliocentric orbit, equipped with accurate means to measure intersatellite ranges, round-trip times and phases of signals coherently retransmitted between members of the constellation. Our goal is to reconstruct the measured trace of the gravitational gradient tensor as accurately as possible. Intersatellite ranges alone are not sufficient for its determination, as they do not account for any rotation of the satellite constellation, which introduces fictitious forces and accelerations. However, measuring signal round-trip time differences among the satellites supplies the necessary observables to estimate, and subtract, the effects of rotation. Utilizing, in addition, the approximate distance and direction from the Sun, it is possible to approach an accuracy of $10^{-24}~{\rm s}^{-2}$ for a constellation with typical intersatellite distances of 1,000 km in an orbit with a 1 astronomical unit semi-major axis. This is deemed sufficient to detect the presence of a galileonic modification of the solar gravitational field.
description: 24 pages, 5 figures, final submitted version after referee comments
ФАКТОРЫ ЭФФЕКТИВНОСТИ ЛОГИСТИЧЕСКИХ РАСПРЕДЕЛИТЕЛЬНЫХ ЦЕНТРОВ
Creators: name: Kaygorodtsev, Artem
name: Rakhmangulov, Aleksandr
Publisher: name: figshare
Year: 2020
Subjects: subject: 150309 Logistics and Supply Chain Management
subject: FOS: Economics and business

description: Factors affecting the efficiency
of the location of a logistics distribution
center at a particular point are considered
in detail
Endemic infections are always possible on regular networks
Creators: name: Del Genio, Charo I.
name: House, Thomas
Publisher: name: arXiv
Year: 2013
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Social and Information Networks (cs.SI)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: We study the dependence of the largest component in regular networks on the clustering coefficient, showing that its size changes smoothly without undergoing a phase transition. We explain this behaviour via an analytical approach based on the network structure, and provide an exact equation describing the numerical results. Our work indicates that intrinsic structural properties always allow the spread of epidemics on regular networks.
description: 5 pages, 4 figures
A Text-based Approach For Link Prediction on Wikipedia Articles
Creators: name: Tran, Anh Hoang
name: Nguyen, Tam Minh
name: Luu, Son T.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: This paper present our work in the DSAA 2023 Challenge about Link Prediction for Wikipedia Articles. We use traditional machine learning models with POS tags (part-of-speech tags) features extracted from text to train the classification model for predicting whether two nodes has the link. Then, we use these tags to test on various machine learning models. We obtained the results by F1 score at 0.99999 and got 7th place in the competition. Our source code is publicly available at this link: https://github.com/Tam1032/DSAA2023-Challenge-Link-prediction-DS-UIT_SAT
description: Accepted by DSAA 2023 Conference in the DSAA Student Competition Section
Josephson physics of spin-orbit coupled elongated Bose-Einstein condensates
Creators: name: Garcia-March, M. A.
name: Mazzarella, G.
name: Dell'Anna, L.
name: Juliá-Díaz, B.
name: Salasnich, L.
name: Polls, A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We consider an ultracold bosonic binary mixture confined in a one-dimensional double-well trap. The two bosonic components are assumed to be two hyperfine internal states of the same atom. We suppose that these two components are spin-orbit coupled between each other. We employ the two-mode approximation starting from two coupled Gross-Pitaevskii equations and derive a system of ordinary differential equations governing the temporal evolution of the inter-well population imbalance of each component and that between the two bosonic species. We study the Josephson oscillations of these spin-orbit coupled Bose-Einstein condensates by analyzing the interplay between the interatomic interactions and the spin-orbit coupling and the self-trapped dynamics of the inter-species imbalance. We show that the dynamics of this latter variable is crucially determined by the relationship between the spin-orbit coupling, the tunneling energy, and the interactions.
description: 14 pages, 8 figures
A Method for Driving an Oscillator at a Quasi-Uniform Velocity
Creators: name: Zmeev, D. E.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Other Condensed Matter (cond-mat.other)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We describe a simple way to drive an actuator, comprising a superconducting coil moving in a static magnetic field, at a quasi-uniform velocity. The main objective is to avoid oscillations in this system with low damping, as they undermine the uniformity of the velocity. The method consists in calculating the force that should be exerted on the coil from the equation of motion and programming a waveform generator to produce the corresponding current through the coil. The method was tested on a device towing a grid through a closely fitted channel filled with superfluid 4He at temperatures below 100 mK. The motion of the grid over the distance of 4.3 cm at 10 cm/s resulted in oscillations of less than 50 μm in amplitude (or less than 1 mm/s in terms of velocity). The method can be applied to any oscillator.
description: 6 pages, 3 figures
Abstraction Level Taxonomy of Programming Language Frameworks
Creators: name: Kahanwal, Dr. Brijender
Publisher: name: arXiv
Year: 2013
Subjects: subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences

description: The main purpose of this article is to describe the taxonomy of computer languages according to the levels of abstraction. There exists so many computer languages because of so many reasons like the evolution of better computer languages over the time; the socio-economic factors as the proprietary interests, commercial advantages; expressive power; ease of use of novice; orientation toward special purposes; orientation toward special hardware; and diverse ideas about most suitability. Moreover, the important common properties of most of these languages are discussed here. No programming language is designed in a vacuity, but it solves some specific kinds of problems. There is a different framework for each problem and best suitable framework for each problem. A single framework is not best for all types of problems. So, it is important to select vigilantly the frameworks supported by the language. The five generation of the computer programming languages are explored in this paper to some extent.
description: 12 pages, 3 figures