bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tunable gigahertz dynamics of low-temperature skyrmion lattice in a chiral magnet
Authors: Lee Oscar , Sahliger Jan , Aqeel Aisha , Khan Safe , Seki Shinichiro , Kurebayashi Hidekazu , Back Christian H 
Published: November 2021

Abstract
Recently, it has been shown that the chiral magnetic insulator Cu2OSeO3 hosts skyrmions in two separated pockets in temperature and magnetic field phase space. It has also been shown that the predominant stabilization mechanism for the low-temperature skyrmion (LTS) phase is via the crystalline anisotropy, opposed to temperature fluctuations that stabilize the well-established high-temperature skyrmion (HTS) phase. Here, we report on a detailed study of LTS generation by field cycling, probed by GHz spin dynamics in Cu2OSeO3. LTSs are populated via a field cycling protocol with the static magnetic field applied parallel to the ⟨100⟩ crystalline direction of plate and cuboid-shaped bulk crystals. By analyzing temperature-dependent broadband spectroscopy data, clear evidence of LTS excitations with clockwise (CW), counterclockwise (CCW), and breathing mode (BR) character at temperatures below T = 40 K are shown. We find that the mode intensities can be tuned with the number of field-cycles below the saturation field. By tracking the resonance frequencies, we are able to map out the field-cycle-generated LTS phase diagram, from which we conclude that the LTS phase is distinctly separated from the high-temperature counterpart. We also study the mode hybridization between the dark CW and the BR modes as a function of temperature. By using two Cu2OSeO3 crystals with different shapes and therefore different demagnetization factors, together with numerical calculations, we unambiguously show that the magnetocrystalline anisotropy plays a central role for the mode hybridization.
Enhancing the hybridization of plasmons in graphene with 2D superconductor collective modes
Authors: Costa A T , Peres N M R 
Published: November 2021

Abstract
We explore ways in which the close proximity between graphene sheets and monolayers of 2D superconductors can lead to hybridization between their collective excitations. We consider heterostructures formed by combinations of graphene sheets and 2D superconductor monolayers. The broad range of energies in which the graphene plasmon can exist, together with its tunability, makes such heterostructures promising platforms for probing the many-body physics of superconductors. We show that the hybridization between the graphene plasmon and the Bardasis–Schrieffer mode of a 2D superconductor results in clear signatures on the near-field reflection coefficient of the heterostructure, which in principle can be observed in scanning near-field microscopy experiments.
Prediction of solar cell materials via unsupervised literature learning
Authors: Zhang Lei , He Mu 
Published: November 2021

Abstract
Despite the significant advancement of the data-driven studies for physical science, the textual data that are numerous in the literature are not fully embraced by the physics and materials community. In this manuscript, we successfully employ the natural language processing (NLP) technique to unsupervisedly predict the existence of solar cell types including the dye-sensitized solar cells and the perovskite solar cells based on literatures published prior to their first discovery without human annotation. Enlightened by this, we further identify possible solar cell material candidates via NLP starting with a comprehensive training database of 3.2 million paper abstracts published before 2021. The NLP model effectively predicts the existing solar cell materials, while an uncommon solar cell material namely PtSe2 is suggested as an appropriate candidate for the future solar cells. Its optoelectronic properties are comprehensive investigated via first-principles calculations to reveal the decent stability and optoelectronic performance of the NLP-predicted candidate. This study demonstrates the viability of the textual data for the data-driven materials prediction and highlights the NLP method as a powerful tool to reliably predict the solar cell materials.
Development and evaluation of the effectiveness of educational material for radiological protection that uses augmented reality and virtual reality to visualise the behaviour of scattered radiation
Authors: Nishi Kazuki , Fujibuchi Toshioh , Yoshinaga Takashi 
Published: November 2021

Abstract
Understanding the behaviour of scattered radiation is important for learning appropriate radiation protection methods, but many existing visualisation systems for radiation require special devices, making it difficult to use them in education. The purpose of this study was to develop teaching material for radiation protection that can help visualise the scattered radiation with augmented reality (AR) and virtual reality (VR) on a web browser, develop a method for using it in education and examine its effectiveness. The distribution of radiation during radiography was calculated using Monte Carlo simulation, and teaching material was created. The material was used in a class for department of radiological technology students and its influence on motivation was evaluated using a questionnaire based on the evaluation model for teaching materials. In addition, text mining was used to evaluate impressions objectively. Educational material was developed that can be used in AR and VR for studying the behaviour of scattered radiation. The results of the questionnaire showed that the average value of each item was more than four on a five-point scale, indicating that the teaching material attracted the interest of users. Through text mining, it could be concluded that there was improved understanding of, and confidence in, radiation protection.
Role of thermal history on atomic structure and ductility of ion-irradiated metallic glasses
Authors: Chen Tzu-Chia , Raya Indah , Shafik Shafik S , Jabbar Abdullah Hasan , Tumanov Dmitry , Surendar Aravindhan , Sevbitov Andrei , Hoi Huynh Tan , Mustafa Yasser Fakri , Vladimirovich Kabanov Oleg , Kadhim Mustafa M , Sajjadifar Sami , Repnikov Nikolay I 
Published: November 2021

Abstract
Maximizing the structural rejuvenation and ductility is one of the most heated debates in the field of metallic glasses (MGs). In this work, molecular dynamics simulation was implemented to model the ion irradiation effects on the Cu60Zr40 MG with different thermal histories and varied structural heterogeneities. The initial results indicated that the performance of an annealing–quench treatment on the MG induces the atomic configurations with different heterogeneities and potential energy values. The subsequent ion irradiation process also demonstrated that an optimized atomic structure was occurred for achieving maximum rejuvenation and ductility in the CuZr glassy alloy. It was unveiled that the intermediate initial heterogeneity provides an efficient pathway for maximizing the atomic rearrangements under the ion irradiation. It was also suggested that the medium population of Cu-centered clusters in the initial state facilitated the atomic rearrangements during the ion irradiation process. The structural characteristics and atomic reconfigurations for attaining the optimum ductility is discussed in details.
Surface energies and relaxation of NiCoCr and NiFeX (X
= Cu, Co or Cr) equiatomic multiprincipal element alloys from first principles calculations
Authors: Li Wei , Peng Xianghe , Ngan Alfonso H W , El-Awady Jaafar A 
Published: November 2021

Abstract
First principles calculations of the energies and relaxation of unreconstructed low-index surfaces, i.e. (001), (011) and (111) surfaces, in NiCoCr and NiFeX (X = Cu, Co or Cr) equiatomic multi-principal element alloys (MPEAs) are presented. The calculations were conducted for 12-layer slabs represented by special quasi-random supercells using the projector augmented wave method within the generalized gradient approximation. While experimental predictions are unavailable for comparison, the calculated surface energies agree fairly well with those from thermodynamic modeling and a bond-cutting model. In addition, the calculations unveil an important surface structure, namely, that the topmost surface layer is in contraction except for the (001) surface of NiFeCr alloy, the next layer below is in extension, and the bulk spacing is gradually recovered from the subsequent layers down. Additionally, the surface contraction is the most pronounced on the (011) plane, being about 4%–10% relative to the bulk spacings. The results presented here can provide an understanding of surface-controlled phenomena such as corrosion, catalytic activities and fracture properties in these equiatomic MPEAs.
Enhanced magnetic performance in exchange-coupled CoFe2O4–LaFeO3 nanocomposites
Authors: Sharma Priyanka , Jain Anjali , Chatterjee Ratnamala 
Published: November 2021

Abstract
Nanocomposite oxide system of (x)CoFe2O4–(100-x)LaFeO3 with different weight percent of core-shell structured CoFe2O4 (x = 0, 20, 40, 50, 80, 100) and LaFeO3 were fabricated, via a two-step sol-gel wet-chemical synthesis technique. The phase formation of the composites was confirmed by x-ray diffraction and the structural parameters of both the phases were attained from the Rietveld refinement results of XRD patterns. The elemental composition and microstructure of the resulting nanocomposites were examined by using energy-dispersive x-ray spectroscopy and high-resolution transmission electron microscopy technique, respectively. The detailed magnetometry studies at 300 K and 5 K reveal that the inter-and intra-phase magnetic interactions affect the saturation magnetization (M
S), remanence magnetization (M
R) and coercivity (H
C) values of this bi-magnetic system. The remarkable feature of ‘pinched magnetic hysteresis loop’ was evidenced in the [(50) CoFe2O4 - (50)LaFeO3] composite, leading to a lesser magnetic loss factor and better magnetic performance of this sample. The report depicts an improved interfacial exchange coupling at 5 K, for the nanocomposites of core-shell morphology and offers an understanding or explanation of improved magnetic performance for the (50)CoFe2O4 - (50)LaFeO3 nanocomposite and opens up an important way to design new multiferroic applications in low magnetic fields.
Controllable synthesis of Mo2C with different morphology and application to electrocatalytic hydrogen evolution reaction
Authors: Chang He-Qiang , Zhang Guo-Hua , Chou Kuo-Chih 
Published: November 2021

Abstract
In order to evaluate the effect of precursors and synthesis strategies on catalytic ability of Mo2C in the hydrogen evolution reaction (HER), four kinds of Mo2C were synthesized using two kinds of MoO3 by two strategies. Compared with the one-step direct carbonization strategy, Mo2C with a large special surface area and a better performance could be synthesized by the two-step strategy composed of a nitridation reaction and a carbonization reaction. Additionally, the as-prepared porous Mo2C nanobelts (NBs) exhibit good electrocatalytic performance with a small overpotential of 165 mV (0.5 M H2SO4) and 124 mV (1 M KOH) at 10 mA cm−2, as well as a Tafel slope of 58 mV dec−1 (0.5 M H2SO4) and 59 mV dec−1 (1 M KOH). The excellent catalytic activity is ascribed to the nano crystallites and porous structure. What’s more, the belt structure also facilitates the charge transport in the materials during the electrocatalytic HER process. Therefore, the two-step strategy provides a new insight into the structural design with superior performance for electrocatalytic HER.
Fabrication of periodic microscale stripes of silver by laser interference induced forward transfer and their SERS properties
Authors: Shen Huijuan , Wang Yaode , Cao Liang , Xie Ying , Wang Lu , Chu Xueying , Shi Kaixi , Wang Shenzhi , Yu Miaomiao , Liu Ri , Zhang Jingran , Li Changli , Weng Zhankun , Wang Zuobin 
Published: November 2021

Abstract
The micro-stripe structure was prepared by laser interference induced forward transfer technique, composed of Ag nano-particles (NPs). The effects of the film thickness with the carbon nano-particles mixed polyimide (CNPs@PI), Ag film thickness, and laser fluence were studied on the transferred micro-stripe structure. The periodic Ag micro-stripe with good resolution was obtained in a wide range of CNPs@PI film thickness from ∼0.5 to ∼1.0 μm for the Ag thin film ∼20 nm. The distribution of the Ag NPs composing the micro-stripe was compact. Nevertheless, the average size of the transferred Ag NPs was increased from ∼41 to ∼197 nm with the change of the Ag donor film from ∼10 to ∼40 nm. With the increase of the laser fluence from 102 to 306 mJ·cm−2 per-beam, the transferred Ag NPs became aggregative, improving the resolution of the corresponding micro-stripe. Finally, the transferred Ag micro-stripe exhibited the significant surface enhanced Raman scattering (SERS) property for rhodamine B (RhB). While the concentration of the RhB reached 10–10 mol·L−1, the Raman characteristic peaks of the RhB were still observed clearly at 622, 1359 and 1649 cm−1. These results indicate that the transferred Ag micro-stripe has potential application as a SERS chip in drug and food detection.
Experimental determination of modulation power of lung tissue for particle therapy
Authors: Burg Jan Michael , Flatten Veronika , Witt Matthias , Derksen Larissa , Weber Uli , Engenhart-Cabillic Rita , Vorwerk Hilke , Zink Klemens , Baumann Kilian-Simon 
Published: November 2021

Abstract
In particle therapy of lung tumors, modulating effects on the particle beam may occur due to the microscopic structure of the lung tissue. These effects are caused by the heterogeneous nature of the lung tissue and cannot be completely taken into account during treatment planning, because these micro structures are too small to be fully resolved in the planning CT. In several publications, a new material parameter called modulation power (P

mod
) was introduced to characterize the effect. For various artificial lung surrogates, this parameter was measured and published by other groups and ranges up to approximately 1000 μm. Studies investigating the influence of the modulation power on the dose distribution during irradiation are using this parameter in the rang of 100–800 μm. More precise measurements for P

mod
on real lung tissue have not yet been published. In this work, the modulation power of real lung tissue was measured using porcine lungs in order to produce more reliable data of P

mod
for real lung tissue. For this purpose, ex-vivo porcine lungs were frozen in a ventilated state and measurements in a carbon ion-beam were performed. Due to the way the lungs were prepared and transferred to a solid state, the lung structures that modulate the beam could also be examined in detail using micro CT imaging. An optimization of the established methods of measuring the modulation power, which takes better account of the typical structures within lung tissue, was developed as well.
Effects of 4d transition metal Pd doping on the magnetic and superconducting properties of 112-type iron pnictide EuFeAs2
Authors: Zhan Xinhui , Yi Xiaolei , Xing Xiangzhuo , Li Meng , Yu Linchao , Huang Song , Feng Jiajia , Meng Yan , Zhou Nan , Liu Xiaobing , Shi Zhixiang 
Published: November 2021

Abstract
The recently discovered 112-type EuFeAs2 compound that shows complex Eu-spin magnetism provides a new platform to study the interplay between superconductivity (SC) and magnetism in iron pnictide superconductors. In this paper, by substituting Fe with the 4d transition metal (TM) Pd, we have synthesized a series of EuFe1−x
Pd
x
As2 (0 ⩽ x ⩽ 0.08) samples and studied the doping effect on SC and magnetism by means of electrical transport and magnetization measurements. The systematic evolution of the lattice parameters indicates that the Pd atoms have been successfully substituted into the Fe sites. With Pd doping, the Fe-related spin density wave transition at

T

m

Fe

in the parent phase is rapidly suppressed, and SC simultaneously emerges, exhibiting a domelike shape with a maximum onset transition temperature

T

c

onset

of around 18.5 K at x = 0.04. On the other hand, the Eu-related antiferromagnetic order at

T

m

Eu

is suppressed very slowly and persists up to x = 0.08, covering the whole SC dome region. Also, the reentrant spin-glass and spin-reorientation transitions below

T

m

Eu

remain unchanged with Pd doping. All these results indicate that the Eu spins have little effect on SC in EuFe1−x
Pd
x
As2. Finally, based on the resistivity and magnetization data, the T − x phase diagram of EuFe1−x
Pd
x
As2 is constructed and compared with those of 3d TMs Co/Ni and La doped ones.
MHD simulations of cold bubble formation from 2/1 tearing mode during massive gas injection in a tokamak
Authors: Zeng Shiyong , Zhu Ping , Izzo V.A. , Li Haolong , Jiang Zhonghe 
Published: November 2021

Abstract
Massive gas injection (MGI) experiments have been carried out in many tokamaks to study disruption dynamics and mitigation schemes. Two events often observed in those experiments are the excitation of the m = 2, n = 1 magnetohydrodynamic mode, and the formation of cold bubble structure in the temperature distribution before the thermal quench (TQ). Here m is the poloidal mode number, n the toroidal mode number. The physics mechanisms underlying those phenomena, however, have not been entirely clear. In this work, our recent NIMROD simulations of the MGI process in a tokamak have reproduced the main features of both events, which has allowed us to examine and establish the causal relation between them. In these simulations, the 3/1 and 2/1 islands are found to form successively after the arrival of impurity ion cold front at the corresponding q = 3 and q = 2 rational surfaces. At the interface between impurity and plasma, a local thin current sheet forms due to an enhanced local pressure gradient and moves inward following the gas cold front, this may contribute to the formation of a dominant 2/1 mode. Following the growth of the 2/1 tearing mode, the impurity penetration into the core region inside the q = 2 surface gives rise to the formation of the cold bubble temperature structure and initiates the final TQ. A subdominant 1/1 mode developed earlier near the q = 1 surface alone does not cause such a cold bubble formation, however, the exact manner of the preceding impurity penetration depends on the nature of the 1/1 mode: kink-tearing or quasi-interchange.
Understanding core tungsten (W) transport and control in an improved high-performance fully non-inductive discharge on EAST
Authors: Shi Shengyu , Chen Jiale , Bourdelle Clarisse , Jian Xiang , Odstrčil Tomáš , Garofalo Andrea M. , Cheng Yunxin , Chao Yan , Zhang Ling , Duan Yanmin , Wu Muquan , Ding Fang , Li Yingying , Huang Juan , Qian Jinping , Gao Xiang , Wan Yuanxi 
Published: November 2021

Abstract
The behavior of heavy/high-Z impurity tungsten (W) in an improved high-performance fully non-inductive discharge on EAST with ITER-like divertor (ILD) is analyzed. It is found that W could be well controlled. The causes of no W accumulation are clarified by analyzing the background plasma parameters and modeling the W transport. It turns out that the electron temperature (T
e) and its gradient are usually high while the toroidal rotation and density peaking of the bulk plasma are small. In this condition, the modeled W turbulent diffusion coefficient is big enough to offset the total turbulent and neoclassical pinch, so that W density profile for zero particle flux will not be very peaked. Combining NEO and TGLF for the W transport coefficient and the impurity transport code STRAHL, not only the core W density profile is predicted but also the radiated information mainly produced by W in the experiment can be closely reconstructed. At last, the physics of controlling W accumulation by electron cyclotron resonance heating (ECRH) is illustrated considering the effects of changed T
e by ECRH on ionization balance and transport of W. It shows that the change of ionization and recombination balance by changed T
e is not enough to explain the experimental observation of W behavior, which should be attributed to the changed W transport. By comparing the W transport coefficients in two kinds of plasmas with different T
e profiles, it is shown that high T
e and its gradient play a key role to generate large turbulent diffusion through increasing the growth rate of linear instability so that W accumulation is prevented.
Background estimate in heavy-ion two-body reactions measured by the MAGNEX spectrometer
Authors: Calabrese S. , Cappuzzello F. , Carbone D. , Cavallaro M. , Agodi C. , Torresi D. , Acosta L. , Bonanno D. , Bongiovanni D. , Borello-Lewin T. , Boztosun I. , Brischetto G. , Calvo D. , Ciraldo I. , Deshmukh N. , de Faria P.N. , Finocchiaro P. , Foti A. , Gallo G. , Hacisalihoglu A. , Iazzi F. , Introzzi R. , Lanzalone G. , Linares R. , Longhitano F. , Presti D. Lo , Medina N. , Muoio A. , Oliveira J.R.B. , Pakou A. , Pandola L. , Pinna F. , Reito S. , Russo G. , Santagati G. , Sgouros O. , Solakci S.O. , Soukeras V. , Souliotis G. , Spatafora A. , Tudisco S. , Zagatto V.A.B. 
Published: November 2021

Abstract
The MAGNEX magnetic spectrometer is nowadays used in the experimental measurements of rare quasi-elastic reactions between heavy ions at intermediate energy within the NUMEN project. The small cross sections involved in such processes under the large yields due to competitive reaction channels have motivated an accurate control of the background sources. In such view, the not ideal particle identification could introduce spurious contributions which have been identified and evaluated in the present analysis.
Optical and mathematical method for studying electrode discharge spots with a liquid electrode
Authors: Tazmeev B Kh , Tsybulevsky V V 
Published: November 2021

Abstract
High-speed visualization of the discharge with a liquid cathode, color image processing were performed. The area of cathode spots concentration was identified. Statistical characteristics of the distribution of cathode spots were obtained in order to determine the range in which the intensity code of the green color channel changes, the polygon function of the empirical distribution of the intensity code for the green color channel. The graphical dependence on the frequency of the cathode spot indication hit into the specified interval of the color intensity code was created.
Numerical study of a model of terahertz collective modes in DNA
Authors: Zakhvataev V E , Volodko O S , Kompaniets L A , Zlobin D V 
Published: November 2021

Abstract
Terahertz density fluctuations in DNA have been recognized to be associated with biological function of DNA and widely studied both experimentally and theoretically. In the present work, we investigate numerically a new model for the terahertz dynamics of density fluctuations in DNA, proposed earlier. This model considers the length scales corresponding to wave numbers up to the position of the maximum of the static structure factor and allows to reflect structural effects caused by the dependence of the static structure factor on wave number. We study the parametric dependencies of the model to elucidate the effect of dlocalization of the dynamics of density fluctuations caused by structural effects.
Investigation rectifier circuits based on the mathematical models in the two-dimensional space
Authors: Hien Nguyen Thi , Zaslavskiy A A 
Published: November 2021

Abstract
The mathematical model for the rectifier circuit using semiconductor diodes is setup in this paper. The properties of the rectifier circuit presented by the ordinary differential equation containing a control parameter K. When K is large enough, the studied equation gives a trajectory approximating to a trajectory of the rectifier circuit above. The theorem about the approximation of these solutions with arbitrary small error (this error can be controlled by increasing K). The usefulness of this model is illustrated via concrete example. This study can to get more profound results in further and investigate an optimal process for an assembly line of rectifiers in electrical engineering.