Ariel Zylberberg, Luciano Paz, P. Roelfsema, S. Dehaene, M. Sigman
We describe the operation of a neuronal device which embodies the computational principles of the `paper-and-pencil' machine envisioned by Alan Turing. The network is based on principles of cortical organization. We develop a plausible solution to implement pointers and investigate how neuronal circuits may instantiate the basic operations involved in assigning a value to a variable (i.e., x=5), in determining whether two variables have the same value and in retrieving the value of a given variable to be accessible to other nodes of the network. We exemplify the collective function of the network in simplified arithmetic and problem solving (blocks-world) tasks. Received: 14 June 2013, Accepted: 9 July 2013; Edited by: G. B. Mindlin; DOI: http://dx.doi.org/10.4279/PIP.050006 Cite as: A Zylberberg, L Paz, P R Roelfsema, S Dehaene, M Sigman, Papers in Physics 5, 050006 (2013)
我们描述了一个神经元装置的操作，它体现了艾伦·图灵设想的“纸笔”机器的计算原理。该网络基于皮层组织原理。我们开发了一个可行的解决方案来实现指针，并研究神经元回路如何实例化涉及到的基本操作，包括为变量赋值(即x=5)，确定两个变量是否具有相同的值，以及检索给定变量的值以供网络的其他节点访问。我们在简化的算法和问题解决(块世界)任务中举例说明了网络的集体功能。收稿日期:2013年6月14日，收稿日期:2013年7月9日;编辑:g.b.明德林;引用全文:A Zylberberg, L Paz, P R Roelfsema, S Dehaene, M Sigman, Papers in Physics 5,050006 (2013)
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T. Wilson, Charlotte R. Pfeifer, N. Mesyngier, D. Durian
The discharge of spherical grains from a hole in the bottom of a right circular cylinder is measured with the entire system underwater. We find that the discharge rate depends on filling height, in contrast to the well-known case of dry non-cohesive grains. It is further surprising that the rate increases up to about twenty five percent, as the hopper empties and the granular pressure head decreases. For deep filling, where the discharge rate is constant, we measure the behavior as a function of both grain and hole diameters. The discharge rate scale is set by the product of hole area and the terminal falling speed of isolated grains. But there is a small-hole cutoff of about two and half grain diameters, which is larger than the analogous cutoff in the Beverloo equation for dry grains. Received: 11 September 2014, Accepted: 10 October 2014; Reviewed by: L. Staron, CNRS, Universite Pierre et Marie Curie, Institut Le Rond d'Alembert, Paris, France; Edited by: L. A. Pugnaloni; DOI: http://dx.doi.org/10.4279/PIP.060009 Cite as: T J Wilson, C R Pfeifer, N Meysingier, D J Durian, Papers in Physics 6, 060009 (2014)
在整个系统处于水下的情况下，测量了球形颗粒从右圆柱体底部的孔中流出的情况。我们发现，与众所周知的干燥无粘性颗粒的情况相反，放电速率取决于填充高度。更令人惊讶的是，当料斗清空，颗粒压头减小时，速率增加到约25%。对于放电速率恒定的深度填充，我们测量了作为颗粒直径和孔径的函数的行为。放电速率尺度由孔洞面积与孤立颗粒最终下落速度的乘积确定。但存在一个约2.5粒直径的小孔截止点，这比Beverloo方程中干粒的类似截止点要大。收稿日期:2014年9月11日，收稿日期:2014年10月10日;评审:L. Staron，法国国家科学研究中心，皮埃尔和玛丽居里大学，法国巴黎达朗贝尔路研究所;编辑:L. A. Pugnaloni;引用全文:T J Wilson, C R Pfeifer, N meyssingier, D J Durian, Papers in Physics, 6,060009 (2014)
{"title":"Granular discharge rate for submerged hoppers","authors":"T. Wilson, Charlotte R. Pfeifer, N. Mesyngier, D. Durian","doi":"10.4279/pip.060009","DOIUrl":"https://doi.org/10.4279/pip.060009","url":null,"abstract":"The discharge of spherical grains from a hole in the bottom of a right circular cylinder is measured with the entire system underwater. We find that the discharge rate depends on filling height, in contrast to the well-known case of dry non-cohesive grains. It is further surprising that the rate increases up to about twenty five percent, as the hopper empties and the granular pressure head decreases. For deep filling, where the discharge rate is constant, we measure the behavior as a function of both grain and hole diameters. The discharge rate scale is set by the product of hole area and the terminal falling speed of isolated grains. But there is a small-hole cutoff of about two and half grain diameters, which is larger than the analogous cutoff in the Beverloo equation for dry grains. Received: 11 September 2014, Accepted: 10 October 2014; Reviewed by: L. Staron, CNRS, Universite Pierre et Marie Curie, Institut Le Rond d'Alembert, Paris, France; Edited by: L. A. Pugnaloni; DOI: http://dx.doi.org/10.4279/PIP.060009 Cite as: T J Wilson, C R Pfeifer, N Meysingier, D J Durian, Papers in Physics 6, 060009 (2014)","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2013-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71010503","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}
Realistic mathematical modeling of voice production has been recently boosted by applications to different fields like bioprosthetics, quality speech synthesis and pathological diagnosis. In this work, we revisit a two-mass model of the vocal folds that includes accurate fluid mechanics for the air passage through the folds and nonlinear properties of the tissue. We present the bifurcation diagram for such a system, focusing on the dynamical properties of two regimes of interest: the onset of oscillations and the normal phonation regime. We also show theoretical support to the nonlinear nature of the elastic properties of the folds tissue by comparing theoretical isofrequency curves with reported experimental data. Received: 2 March 2013, Accepted: 5 June 2013; Edited by: G. Mindlin; DOI: http://dx.doi.org/10.4279/PIP.050004 Cite as: M F Assaneo, M A Trevisan, Papers in Physics 5, 050004 (2013)
语音生成的真实数学建模最近在生物修复、高质量语音合成和病理诊断等不同领域的应用得到了推动。在这项工作中，我们重新审视了声带的双质量模型，该模型包括空气通过褶皱和组织非线性特性的精确流体力学。我们提出了这样一个系统的分岔图，重点关注两个感兴趣的制度的动力学性质:振荡的开始和正常发声制度。我们还通过将理论等频曲线与实验数据进行比较，为褶皱组织弹性特性的非线性提供了理论支持。收稿日期:2013年3月2日，收稿日期:2013年6月5日;编辑:G.明德林;引用全文:M F Assaneo, M A Trevisan, Papers in Physics 5,050004 (2013)
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P. Grondona, H. O. Rocco, D. Iriarte, J. Pomarico, H. Ranea-Sandoval, G. Bilmes
We report a series of experiments on laser pulsed photoacoustic excitationin turbid polymer samples addressed to evaluate the sound speed in the samples and the presence of inhomogeneities in the bulk. We describe a system which allows the direct measurement of the speed of the detected waves by engraving the surface of the piece under study with a fiduciary pattern of black lines..We also describe how this pattern helps to enhance the sensitivity for the detection of an inhomogeneity in the bulk. These two facts are useful for studies in soft matter systems including, perhaps, biological samples. We have performed an experimental analysis on Grilon® samples in different situations and we show the limitations of the method. Received: 7 December 2012, Accepted: 19 June 2013; Reviewed by: V. Lakshminarayanan, Waterloo University, Canada; Edited by: J. J. Niemela; DOI: http://dx.doi.org/10.4279/PIP.050005 Cite as: P. Grondona, H. O. Di Rocco, D. I. Iriarte, J. A. Pomarico, H. F. Ranea-Sandoval, G. M. Bilmes , Papers in Physics 5, 050005 (2013)
我们报道了在混浊聚合物样品中进行激光脉冲光声激励的一系列实验，以评估样品中的声速和体中不均匀性的存在。我们描述了一种系统，该系统允许通过在所研究的工件表面雕刻带有黑线的信任模式来直接测量被检测波的速度。我们还描述了这种模式如何有助于提高检测批量不均匀性的灵敏度。这两个事实对软物质系统的研究很有用，可能包括生物样品。我们对不同情况下的Grilon®样品进行了实验分析，并显示了该方法的局限性。收稿日期:2012年12月7日，收稿日期:2013年6月19日;审评人:V. Lakshminarayanan，滑铁卢大学，加拿大;编辑:j·j·尼梅拉;引用自:p.g rondona, h.o. Di Rocco, d.i. Iriarte, j.a. Pomarico, h.f. Ranea-Sandoval, g.m. Bilmes，《物理学论文》5,050005 (2013)
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María Laura Fernández, M. Otero, N. Schweigmann, H. Solari
We discuss the histo ric mortality record corresponding to the initial focus of the yellow fever epidemic outbreak registered in Buenos Aires during the year 1871 as compared to simulations of a stochastic population dynamics model. This model incorporates the biology of the urban vector of yellow fever, the mosquito Aedes aegypti , the stages of the disease in the human being as well as the spatial extension of the epidemic outbreak. After introducing the historical context and the restrictions it puts on initial conditions and ecological parameters, we discuss the general features of the simulation and the dependence on initial conditions and available sites for breeding the vector. We discuss the sensitivity, to the free parameters, of statistical estimators such as: final death toll, day of the year when the outbreak reached half the total mortality and the normalized daily mortality, showing some striking regularities. The model is precise and accurate enough to discuss the truthfulness of the presently accepted historic discussions of the epidemic causes, showing that there are more likely scenarios for the historic facts. Received: 9 October 2012, Accepted: 1 March 2013; Edited by: G. Mindlin; DOI: http://dx.doi.org/10.4279/PIP.050002 Cite as: M L Fernandez, M Otero, N Schweigmann, H G Solari , Papers in Physics 5, 050002 (2013)
我们讨论了1871年布宜诺斯艾利斯登记的黄热病疫情爆发初始焦点对应的历史死亡率记录，并与随机种群动态模型的模拟进行了比较。该模型结合了黄热病的城市传播媒介——埃及伊蚊的生物学特性、人类患病的阶段以及疫情爆发的空间扩展。在介绍了历史背景及其对初始条件和生态参数的限制之后，我们讨论了模拟的一般特征以及对初始条件和繁殖载体可用地点的依赖。我们讨论了统计估计量对自由参数的敏感性，如:最终死亡人数、爆发达到总死亡率一半的年份日期和标准化的每日死亡率，显示出一些显著的规律。该模型足够精确和准确，可以讨论目前公认的关于流行病原因的历史讨论的真实性，表明历史事实有更多可能的情景。收稿日期:2012年10月9日，收稿日期:2013年3月1日;编辑:G.明德林;引用全文:M L Fernandez, M Otero, N Schweigmann, H G Solari, Papers in Physics 5, 050002 (2013)
{"title":"A mathematically assisted reconstruction of the initial focus of the yellow fever outbreak in Buenos Aires (1871)","authors":"María Laura Fernández, M. Otero, N. Schweigmann, H. Solari","doi":"10.4279/PIP.050002","DOIUrl":"https://doi.org/10.4279/PIP.050002","url":null,"abstract":"We discuss the histo ric mortality record corresponding to the initial focus of the yellow fever epidemic outbreak registered in Buenos Aires during the year 1871 as compared to simulations of a stochastic population dynamics model. This model incorporates the biology of the urban vector of yellow fever, the mosquito Aedes aegypti , the stages of the disease in the human being as well as the spatial extension of the epidemic outbreak. After introducing the historical context and the restrictions it puts on initial conditions and ecological parameters, we discuss the general features of the simulation and the dependence on initial conditions and available sites for breeding the vector. We discuss the sensitivity, to the free parameters, of statistical estimators such as: final death toll, day of the year when the outbreak reached half the total mortality and the normalized daily mortality, showing some striking regularities. The model is precise and accurate enough to discuss the truthfulness of the presently accepted historic discussions of the epidemic causes, showing that there are more likely scenarios for the historic facts. Received: 9 October 2012, Accepted: 1 March 2013; Edited by: G. Mindlin; DOI: http://dx.doi.org/10.4279/PIP.050002 Cite as: M L Fernandez, M Otero, N Schweigmann, H G Solari , Papers in Physics 5, 050002 (2013)","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2013-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71009799","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}
With the aim of establishing a criterion for identifying when a lipid bilayer has reached steady state using the molecular dynamics simulation technique, lipid bilayers of different composition in their liquid crystalline phase were simulated in aqueous solution in presence of CaCl as electrolyte, at different concentration levels. In this regard, we used two different lipid bilayer systems: one composed by 288 DPPC (DiPalmitoylPhosphatidylCholine) and another constituted by 288 DPPS (DiPalmitoylPhosphatidylSerine). In this sense, for both type of lipid bilayers, we have studied the temporal evolution of some lipids properties, such as the surface area per lipid, the deuterium order parameter, the lipid hydration and the lipid-calcium coordination. From their analysis, it became evident how each property has a different time to achieve equilibrium. The following order was found, from faster property to slower property: coordination of ions deuterium order parameter area per lipid hydration. Consequently, when the hydration of lipids or the mean area per lipid are stable we can ensure that the lipid membrane has reached the steady state. Received: 3 September 2012, Accepted: 24 October 2012; Edited by: M. C. Barbosa; DOI: http://dx.doi.org/10.4279/PIP.040005 Cite as: R. D. Porasso, J. J. Lopez Cascales, Papers in Physics 4, 040005 (2012)
为了利用分子动力学模拟技术建立一个识别脂质双分子层何时达到稳态的标准，在以氯化钙为电解质存在的水溶液中，以不同浓度水平模拟了不同组成的液晶相脂质双分子层。在这方面，我们使用了两种不同的脂质双分子层系统:一种由288 DPPC(双棕榈酰磷脂酰胆碱)组成，另一种由288 DPPS(双棕榈酰磷脂酰丝氨酸)组成。从这个意义上说，对于这两种类型的脂质双层，我们研究了一些脂质性质的时间演变，如每脂质表面积、氘序参数、脂质水合作用和脂质钙配位。从他们的分析中，很明显，每个属性如何有不同的时间来达到平衡。从快到慢的顺序是:离子的配位氘的顺序，每次脂质水化参数面积。因此，当脂质的水合作用或每脂质的平均面积稳定时，我们可以确保脂膜达到稳定状态。收稿日期:2012年9月3日，收稿日期:2012年10月24日;编辑:M. C. Barbosa;引用如下:r.d. Porasso, j.j. Lopez Cascales, Papers in Physics 4, 040005 (2012)
{"title":"A criterion to identify the equilibration time in lipid bilayer simulations","authors":"R. D. Porasso, J. Cascales","doi":"10.4279/PIP.040005","DOIUrl":"https://doi.org/10.4279/PIP.040005","url":null,"abstract":"With the aim of establishing a criterion for identifying when a lipid bilayer has reached steady state using the molecular dynamics simulation technique, lipid bilayers of different composition in their liquid crystalline phase were simulated in aqueous solution in presence of CaCl as electrolyte, at different concentration levels. In this regard, we used two different lipid bilayer systems: one composed by 288 DPPC (DiPalmitoylPhosphatidylCholine) and another constituted by 288 DPPS (DiPalmitoylPhosphatidylSerine). In this sense, for both type of lipid bilayers, we have studied the temporal evolution of some lipids properties, such as the surface area per lipid, the deuterium order parameter, the lipid hydration and the lipid-calcium coordination. From their analysis, it became evident how each property has a different time to achieve equilibrium. The following order was found, from faster property to slower property: coordination of ions deuterium order parameter area per lipid hydration. Consequently, when the hydration of lipids or the mean area per lipid are stable we can ensure that the lipid membrane has reached the steady state. Received: 3 September 2012, Accepted: 24 October 2012; Edited by: M. C. Barbosa; DOI: http://dx.doi.org/10.4279/PIP.040005 Cite as: R. D. Porasso, J. J. Lopez Cascales, Papers in Physics 4, 040005 (2012)","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2012-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71009427","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}
Water in plant xylem is often superheated, and therefore in a meta-stable state. Under certain conditions, it may suddenly turn from the liquid to the vapor state. This cavitation process produces acoustic emissions. We report the measurement of ultrasonic acoustic emissions (UAE) produced by natural and induced cavitation in corn stems. We induced cavitation and UAE in vivo , in well controlled and reproducible experiments, by irradiating the bare stem of the plants with a continuous-wave laser beam. By tracing the source of UAE, we were able to detect absorption and frequency filtering of the UAE propagating through the stem. This technique allows the unique possibility of studying localized embolism of plant conduits, and thus to test hypotheses on the hydraulic architecture of plants. Based on our results, we postulate that the source of UAE is a transient "cavity oscillation"' triggered by the disruptive effect of cavitation inception. Received: 14 March 2011, Accepted: 23 April 2012; Edited by: V. Lakshminarayanan; Reviewed by: C. Negreira, Laboratorio de Acustica Ultrasonora, Universidad de la Republica, Uruguay; DOI: http://dx.doi.org/10.4279/PIP.040003 Cite as: E. Fernandez, R. J. Fernandez, G. M. Bilmes, Papers in Physics 4, 040003 (2012)
植物木质部中的水经常处于过热状态，因此处于亚稳定状态。在一定条件下，它可能突然从液体变成蒸汽状态。这个空化过程产生声发射。我们报告了超声波声发射(UAE)的测量产生的自然和诱导空化在玉米茎。在控制良好且可重复的实验中，我们通过连续波激光束照射植物的裸茎，在体内诱导空化和UAE。通过追踪阿联酋的来源，我们能够检测到阿联酋通过茎传播的吸收和频率滤波。这项技术允许研究植物导管局部栓塞的独特可能性，从而测试植物水力结构的假设。根据我们的研究结果，我们假设阿联酋的来源是由空化开始的破坏效应引发的瞬态“空腔振荡”。收稿日期:2011年3月14日，收稿日期:2012年4月23日;编辑:V. Lakshminarayanan;审查人:C. Negreira，乌拉圭共和国大学超声声学实验室;引用出处:E. Fernandez, R. J. Fernandez, G. M. Bilmes, Papers in Physics 4, 040003 (2012)
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We determine the flow structure in an axisymmetric diffuser or expansion region connecting two cylindrical pipes when the inlet flow is a solid body rotation with a uniform axial flow of speeds and U, respectively. A quasi-cylindrical approximation is made in order to solve the steady Euler equation, mainly the Bragg-Hawthorne equation. As in our previous work on the cylindrical region downstream [R Gonzalez et al., Phys. Fluids 20, 24106 (2008); R. Gonzalez et al., Phys. Fluids 22, 74102 (2010), R Gonzalez et al., J. Phys.: Conf. Ser. 296, 012024 (2011)], the steady flow in the transition region shows a Beltrami flow structure. The Beltrami flow is defined as a field that satisfies , with . We say that the flow has a Beltrami flow structure when it can be put in the form , being U and constants, i.e it is the superposition of a solid body rotation and translation with a Beltrami one. Therefore, those findings about flow stability hold. The quasi-cylindrical solutions do not branch off and the results do not depend on the chosen transition profile in view of the boundary conditions considered. By comparing this with our earliest work, we relate the critical Rossby number (stagnation) to the corresponding one at the fold [J. D. Buntine et al., Proc. R. Soc. Lond. A 449, 139 (1995)]. Received: 29 August 2011,, Accepted: 29 February 2012; Edited by: J-P. Hulin; DOI: http://dx.doi.org/10.4279/PIP.040002 Cite as: R Gonzalez, R Page, A S Sartarelli , Papers in Physics 4, 040002 (2012)
确定了进口流为匀速轴向流的固体旋转流时，轴对称扩压器或连接两圆柱管的膨胀区内的流动结构。为了求解稳定欧拉方程，主要是Bragg-Hawthorne方程，采用了准柱面近似。正如我们之前对下游圆柱形区域的研究[R Gonzalez et al.， Phys]。流体20,24106 (2008);R. Gonzalez等人，物理学。流体力学学报，2009(4):559 - 564。[j] . Conf. Ser. 296, 012024(2011)]，过渡区的稳定流表现为Beltrami流结构。Beltrami流被定义为满足的字段。我们说流具有贝尔特拉米流结构，当它可以表示为U和常数的形式时，即它是实体旋转和平移与贝尔特拉米流的叠加。因此，这些关于流动稳定性的发现是成立的。考虑到所考虑的边界条件，拟柱解不分叉，结果不依赖于所选择的过渡曲线。通过与我们最早的工作进行比较，我们将临界罗斯比数(停滞)与相应的褶皱数联系起来[J]。D. Buntine et al.， Proc R. Soc。Lond。[A]; [c];收稿日期:2011年8月29日;收稿日期:2012年2月29日;编辑:J-P。Hulin;引用本文:R Gonzalez, R Page, A S Sartarelli, Papers in Physics 4, 040002 (2012)
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Martín Caldarola, Victor A. Bettachini, A. Rieznik, Pablo G. Konig, M. E. Masip, D. Grosz, A. Bragas
We present a high-speed wavelength tunable photonic crystal fiber-based source capable of generating tunable femtosecond solitons in the infrared region. Through measurements and numerical simulation, we show that both the pulsewidth and the spectral width of the output pulses remain nearly constant over the entire tuning range from 860 to 1160 nm. This remarkable behavior is observed even when pump pulses are heavily chirped (7400 fs^2), which allows to avoid bulky compensation optics, or the use of another fiber, for dispersion compensation usually required by the tuning device. Received: 7 July 2011, Accepted: 1 February 2012; Edited by: A. Goni; Reviewed by: J. Chavez Boggio, Leibniz Institut fur Astrophysik Potsdam, Germany; DOI: http://dx.doi.org/10.4279/PIP.040001 Cite as: M. Caldarola, V. A. Bettachini, A. A. Rieznik, P. G. Konig, M. E. Masip, D. F. Grosz, A. V. Bragas , Papers in Physics 4, 040001 (2012)
我们提出了一种高速波长可调谐的光子晶体光纤源，能够在红外区域产生可调谐飞秒孤子。通过测量和数值模拟，我们发现在860 ~ 1160 nm的整个调谐范围内，输出脉冲的脉宽和谱宽几乎保持不变。即使在泵浦脉冲啁啾严重(7400 fs^2)的情况下，也可以观察到这种显著的行为，这可以避免笨重的补偿光学器件，或者使用另一根光纤，用于调谐装置通常需要的色散补偿。收稿日期:2011年7月7日;收稿日期:2012年2月1日;编辑:A. Goni;评审:J. Chavez Boggio，德国波茨坦莱布尼茨天体物理研究所;DOI: http://dx.doi.org/10.4279/PIP.040001引文为:M. Caldarola, V. A. Bettachini, A. A. Rieznik, P. G. Konig, M. E. Masip, D. F. Grosz, A. V. Bragas，《物理学论文》4,040001 (2012)
{"title":"High-speed tunable photonic crystal fiber-based femtosecond soliton source without dispersion pre-compensation","authors":"Martín Caldarola, Victor A. Bettachini, A. Rieznik, Pablo G. Konig, M. E. Masip, D. Grosz, A. Bragas","doi":"10.4279/PIP.040001","DOIUrl":"https://doi.org/10.4279/PIP.040001","url":null,"abstract":"We present a high-speed wavelength tunable photonic crystal fiber-based source capable of generating tunable femtosecond solitons in the infrared region. Through measurements and numerical simulation, we show that both the pulsewidth and the spectral width of the output pulses remain nearly constant over the entire tuning range from 860 to 1160 nm. This remarkable behavior is observed even when pump pulses are heavily chirped (7400 fs^2), which allows to avoid bulky compensation optics, or the use of another fiber, for dispersion compensation usually required by the tuning device. Received: 7 July 2011, Accepted: 1 February 2012; Edited by: A. Goni; Reviewed by: J. Chavez Boggio, Leibniz Institut fur Astrophysik Potsdam, Germany; DOI: http://dx.doi.org/10.4279/PIP.040001 Cite as: M. Caldarola, V. A. Bettachini, A. A. Rieznik, P. G. Konig, M. E. Masip, D. F. Grosz, A. V. Bragas , Papers in Physics 4, 040001 (2012)","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2012-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71009270","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}
A Commentary on the paper by S. Bustinagorry and A. B. Kolton [ Pap. Phys. 2, 020008 (2010) ]. Received: 25 November 2010, Accepted: 6 January 2011; Edited by: A. Vindigni; DOI: 10.4279/PIP.020009
{"title":"Commentary on \"Anisotropic finite-size scaling of an elastic string at the depinning threshold in a random-periodic medium\"","authors":"A. A. Fedorenko","doi":"10.4279/PIP.020009","DOIUrl":"https://doi.org/10.4279/PIP.020009","url":null,"abstract":"A Commentary on the paper by S. Bustinagorry and A. B. Kolton [ Pap. Phys. 2, 020008 (2010) ]. Received: 25 November 2010, Accepted: 6 January 2011; Edited by: A. Vindigni; DOI: 10.4279/PIP.020009","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71009643","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}
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