发布求助
文献互助 智能选刊 最新文献

EPL (Europhysics Letters)最新文献

筛选
英文 中文
Effective-parametric resonance in a non-oscillating system 非振荡系统中的有效参数共振
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/30006
M. Clerc, C. Falcón, C. Fernández-Oto, E. Tirapegui
{"title":"Effective-parametric resonance in a non-oscillating system","authors":"M. Clerc, C. Falcón, C. Fernández-Oto, E. Tirapegui","doi":"10.1209/0295-5075/98/30006","DOIUrl":"https://doi.org/10.1209/0295-5075/98/30006","url":null,"abstract":"We present a mechanism for the generation of oscillations and nonlinear parametric amplification in a non-oscillating system, which we term effective-parametric resonance. Sustained oscillations appear at a controlled amplitude and frequency, related directly to the external forcing parameters. We present an intuitive explanation for this phenomenon, based on an effective equation for a driven oscillation and discuss its relation to other approaches. More precisely, a high-frequency forcing can generate an effective oscillator, which may have a parametric resonance with the applied forcing. We point out the main ingredients for the development of effective-parametric resonance in non-oscillating systems and show its existence in a simple model. Theoretically, we calculate the appearance of this nonlinear oscillation by computing its stability curve, which is confirmed by numerical simulations and experimental studies on a vertically driven pendulum.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129279514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 8
Giant enhancement in effective piezoelectric sensitivity by pyroelectric coupling 热释电耦合对有效压电灵敏度的显著增强
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/47001
R. Lakes
{"title":"Giant enhancement in effective piezoelectric sensitivity by pyroelectric coupling","authors":"R. Lakes","doi":"10.1209/0295-5075/98/47001","DOIUrl":"https://doi.org/10.1209/0295-5075/98/47001","url":null,"abstract":"We report stable two-layer composites that exhibit large enhancement of effective piezoelectric sensitivity to more than 20000 pC/N in the presence of a thermal gradient. They are based on coupled fields in the non-equilibrium presence of energy flux that is modulated by force. Thermal flux is modulated by a granular contact layer so that electric polarization of pyroelectric origin contributes to stress-generated electric polarization. Effective piezoelectric sensitivity is enhanced by at least two orders of magnitude and is higher than that of known commercial and research materials. The result illustrates the potential of relaxing the usual assumption of equilibrium in the presence of a coupled field to attain extremely high effective properties.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131221871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Curved trajectories of actin-based motility in two dimensions 二维中基于肌动蛋白的运动曲线轨迹
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/38005
Fu-Lai Wen, K. Leung, Hsuan-Yi Chen
{"title":"Curved trajectories of actin-based motility in two dimensions","authors":"Fu-Lai Wen, K. Leung, Hsuan-Yi Chen","doi":"10.1209/0295-5075/98/38005","DOIUrl":"https://doi.org/10.1209/0295-5075/98/38005","url":null,"abstract":"Recent experiments have reported fascinating geometrical trajectories for actin-based motility of bacteria Listeria monocytogenes and functionalized beads. To understand the physical mechanism for these trajectories, we constructed a phenomenological model to study the motion of an actin-propelled disk in two dimensions. In our model, the force and actin density on the surface of the disk are influenced by the translation and rotation of the disk, which in turn is induced by the asymmetric distributions of those densities. We show that this feedback can destabilize a straight trajectory, leading to circular, S-shape and other geometrical trajectories observed in the experiments through bifurcations in the distributions of the force and actin density. The relation between our model and the models for self-propelled deformable particles is emphasized and discussed.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116515144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Structure and band gap tuning of transparent (Ba1−xSrx)SnO3 thin films epitaxially grown on MgO substrates MgO衬底外延生长透明(Ba1−xSrx)SnO3薄膜的结构和带隙调谐
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/47010
Qinzhuang Liu, Bing Li, Jianjun Liu, Hong Li, Zhongliang Liu, Kai Dai, Guangping Zhu, Peng Zhang, Feng Chen, J. Dai
{"title":"Structure and band gap tuning of transparent (Ba1−xSrx)SnO3 thin films epitaxially grown on MgO substrates","authors":"Qinzhuang Liu, Bing Li, Jianjun Liu, Hong Li, Zhongliang Liu, Kai Dai, Guangping Zhu, Peng Zhang, Feng Chen, J. Dai","doi":"10.1209/0295-5075/98/47010","DOIUrl":"https://doi.org/10.1209/0295-5075/98/47010","url":null,"abstract":"(Ba1-xSrx)SnO3 (x=0–1) (BSSO) films were epitaxially grown on MgO substrates by pulsed laser deposition. X-ray diffraction, atomic force microcopy, and optical transmittance investigations reveal that the lattice and band structure properties of the BSSO films can be modified significantly by changing the Sr content. With increasing Sr content from 0 to 1 in films, the lattice parameters decrease from 4.123 to 4.037 Å gradually, while the optical band gaps energy increases from 3.50 to 4.27 eV linearly, which was attributed to the octahedral tilting distortion pushing up the minimum of conduction band. This large structure and band gap tuning of BSSO films are promising for desired applications in the thin-film architecture.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122414996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 34
Immunizing complex networks with limited budget 用有限的预算免疫复杂的网络
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/38004
Baharan Mirzasoleiman, Mahmoudreza Babaei, M. Jalili
{"title":"Immunizing complex networks with limited budget","authors":"Baharan Mirzasoleiman, Mahmoudreza Babaei, M. Jalili","doi":"10.1209/0295-5075/98/38004","DOIUrl":"https://doi.org/10.1209/0295-5075/98/38004","url":null,"abstract":"In this letter we studied the epidemic spreading on scale-free networks assuming a limited budget for immunization. We proposed a general model in which the immunity of an individual against the disease depends on its immunized friends in the network. Furthermore, we considered the possibility that each individual might be eager to pay a price to buy the vaccine and become immune against the disease. Under these assumptions we proposed an algorithm for improving the performance of all previous immunization algorithms. We also introduced a heuristic extension of the algorithm, which works well in scale-free networks.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133492291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 16
Strong excitons in novel two-dimensional crystals: Silicane and germanane 新型二维晶体中的强激子:硅烷和锗烷
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/37004
O. Pulci, P. Gori, M. Marsili, V. Garbuio, R. Sole, F. Bechstedt
{"title":"Strong excitons in novel two-dimensional crystals: Silicane and germanane","authors":"O. Pulci, P. Gori, M. Marsili, V. Garbuio, R. Sole, F. Bechstedt","doi":"10.1209/0295-5075/98/37004","DOIUrl":"https://doi.org/10.1209/0295-5075/98/37004","url":null,"abstract":"We show by first-principles calculations that, due to depressed screening and enhanced two-dimensional confinement, excitonic resonances with giant oscillator strength appear in hydrogenated Si and Ge layers, which qualitatively and quantitatively differ from those of graphane. Their large exciton binding energies and oscillator strengths make them promising for observation of novel physical effects and application in optoelectronic devices on the nanoscale.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126029805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 105
Conductivity and incommensurate antiferromagnetism of Fe1.02Se0.10Te0.90 under pressure Fe1.02Se0.10Te0.90在压力下的电导率和不相称的反铁磁性
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/37002
N. Katayama, K. Matsubayashi, Y. Nomura, S. Ji, J. Leão, M. Green, T. Sato, Y. Uwatoko, M. Fujita, K. Yamada, R. Arita, S. Lee
{"title":"Conductivity and incommensurate antiferromagnetism of Fe1.02Se0.10Te0.90 under pressure","authors":"N. Katayama, K. Matsubayashi, Y. Nomura, S. Ji, J. Leão, M. Green, T. Sato, Y. Uwatoko, M. Fujita, K. Yamada, R. Arita, S. Lee","doi":"10.1209/0295-5075/98/37002","DOIUrl":"https://doi.org/10.1209/0295-5075/98/37002","url":null,"abstract":"By performing resistivity, bulk susceptibility and neutron diffraction on single crystals of Fe1.02Se0.10Te0.90 under pressure, we show that an external pressure can enhance both conductivity and magnetism simultaneously. Surprisingly, the pressure-induced magnetic order is nearly three-dimensional, and incommensurate along both the c-axis and the a-axis, which is accompanied by a structural phase separation. Our powder neutron diffraction data show that the Fe(Se, Te)4 tetrahedron becomes more regular under pressure, which is consistent with the enhancement of the metallicity but is counterintuitive to the three-dimensional magnetic order.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"183 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116482256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
A fundamental Lagrangian approach to transformation acoustics and spherical spacetime cloaking 变换声学和球形时空隐身的基本拉格朗日方法
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/34002
M. M. Tung
{"title":"A fundamental Lagrangian approach to transformation acoustics and spherical spacetime cloaking","authors":"M. M. Tung","doi":"10.1209/0295-5075/98/34002","DOIUrl":"https://doi.org/10.1209/0295-5075/98/34002","url":null,"abstract":"Transformation acoustics centers on the construction of advanced acoustic devices by combining mathematical transformation techniques with the engineering of acoustic metamaterials. We show how differential-geometric methods together with a variational principle form the basis of a powerful framework to control acoustic waves as desired. This formalism is required to leave the acoustic wave equation invariant under coordinate transformations and is shown to consist of a proposed acoustic Lagrangian function on a smooth spacetime manifold. As an immediate consequence, we can derive the general constitutive relations between the acoustic parameters (bulk modulus and mass-density tensor) of the physical and virtual spaces under consideration. We conclude with a practical application of this theory by presenting acoustic spherical cloaking with time dilation.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133086475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 11
Photon bunching in chaotic fields with uni-dimensional probability density 一维概率密度混沌场中的光子聚束
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/44007
V. Degiorgio
{"title":"Photon bunching in chaotic fields with uni-dimensional probability density","authors":"V. Degiorgio","doi":"10.1209/0295-5075/98/44007","DOIUrl":"https://doi.org/10.1209/0295-5075/98/44007","url":null,"abstract":"In a recent experiment the intensity correlation function of twin beams generated by spontaneous parametric down-conversion was found to present a ratio B between the zero-delay value and the infinite-delay value equal to 3, at variance with the bunching ratio B=2 of standard chaotic fields characterized by a two-dimensional Gaussian probability density. In this letter it is pointed out that, for the class of chaotic fields characterized by a fixed phase and a zero-average fluctuating amplitude with a uni-dimensional Gaussian probability density, B is equal to 3, and it is argued that the spontaneous parametric down-conversion field belongs to this latter class, thus giving a simple quantitative explanation to the reported experimental results.","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115807116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Comment on “Quantum effects in spontaneous emission by a relativistic, undulating electron beam” by Robb G. R. M. and Bonifacio R. 对Robb G. R. M.和Bonifacio R.的“相对论性波动电子束自发辐射中的量子效应”的评论。
EPL (Europhysics Letters) Pub Date : 2012-05-01 DOI: 10.1209/0295-5075/98/44001
G. Geloni, V. Kocharyan, E. Saldin
{"title":"Comment on “Quantum effects in spontaneous emission by a relativistic, undulating electron beam” by Robb G. R. M. and Bonifacio R.","authors":"G. Geloni, V. Kocharyan, E. Saldin","doi":"10.1209/0295-5075/98/44001","DOIUrl":"https://doi.org/10.1209/0295-5075/98/44001","url":null,"abstract":"In a recent letter, Robb and Bonifacio [1] claimed that a previously neglected quantum effect results in noticeable changes in the evolution of the energy distribution associated with spontaneous emission in long undulators. They revisited theoretical models used to describe the emission of radiation by relativistic electrons as a continuous diffusive process, and claimed that a drift-diffusion approach can only be used when the parameter =Nw ω/(γmc ) is much smaller than unity, whereNw is the number of undulator periods, is the reduced Planck constant, ω is the photon frequency, γ the relativistic Lorentz factor, m the electron rest mass and c the speed of light. In that work it is argued that when 1, a drift-diffusion equation is no more sufficient to describe the evolution of the distribution of electron momenta, which “occurs as discrete momentum groups according to a Poisson distribution”. However, these results are based on a one-dimensional model of the spontaneous radiation emission. Such model does not account for the angular distribution of the radiation, but only for the emission on axis, which is characterized by an overall relative bandwidth ∼ 1/Nw. In contrast to this, the electron recoil related with the quantized nature of photons depends on the entire angular","PeriodicalId":171520,"journal":{"name":"EPL (Europhysics Letters)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124984746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信