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Yuri S. Kivshar

Bio: Yuri S. Kivshar is an academic researcher from Australian National University. The author has contributed to research in topics: Metamaterial & Soliton. The author has an hindex of 126, co-authored 1845 publications receiving 79415 citations. Previous affiliations of Yuri S. Kivshar include Technische Universität Darmstadt & Los Alamos National Laboratory.


Papers
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TL;DR: A non-trivial link between these two phenomena is revealed, through the Fano interference between Bragg scattering and disorder-induced scattering, that triggers both localization and de-localization in random systems.
Abstract: Light localization in disordered systems and Bragg scattering in regular periodic structures are considered traditionally as two entirely opposite phenomena: disorder leads to degradation of coherent Bragg scattering whereas Anderson localization is suppressed by periodicity. Here we reveal a non-trivial link between these two phenomena, through the Fano interference between Bragg scattering and disorder-induced scattering, that triggers both localization and de-localization in random systems. We find unexpected transmission enhancement and spectrum inversion when the Bragg stop-bands are transformed into the Bragg pass-bands solely owing to disorder. Fano resonances are always associated with coherent scattering in regular systems, but our discovery of disorder-induced Fano resonances may provide novel insights into many features of the transport phenomena of photons, phonons, and electrons. Owning to ergodicity, the Fano resonance is a fingerprint feature for any realization of the structure with a certain degree of disorder.

102 citations

Journal ArticleDOI
01 Mar 2017-Small
TL;DR: Polymeric chains of subwavelength silicon nanodisks are studied and it is demonstrated that these chains can support two types of topological edge modes based on magnetic and electric Mie resonances, and their topological properties are fully dictated by the spatial arrangement of the nanoparticles in the chain.
Abstract: Recently introduced field of topological photonics aims to explore the concepts of topological insulators for novel phenomena in optics. Here polymeric chains of subwavelength silicon nanodisks are studied and it is demonstrated that these chains can support two types of topological edge modes based on magnetic and electric Mie resonances, and their topological properties are fully dictated by the spatial arrangement of the nanoparticles in the chain. It is observed experimentally and described how theoretically topological phase transitions at the nanoscale define a change from trivial to nontrivial topological states when the edge mode is excited.

102 citations

Journal ArticleDOI
TL;DR: A relation between stationary soliton solutions of the model and solitons of the discrete nonlinear Schrödinger (DNLS) equation is demonstrated, and approximate solutions forsolitons whose width is large in comparison to the lattice spacing are derived, using a continuum counterpart ofThe discrete equations.
Abstract: Dynamics of a chain of interacting parity-time-invariant nonlinear dimers is investigated. A dimer is built as a pair of coupled elements with equal gain and loss. A relation between stationary soliton solutions of the model and solitons of the discrete nonlinear Schrodinger (DNLS) equation is demonstrated. Approximate solutions for solitons whose width is large in comparison to the lattice spacing are derived, using a continuum counterpart of the discrete equations. These solitons are mobile, featuring nearly elastic collisions. Stationary solutions for narrow solitons, which are immobile due to the pinning by the effective Peierls-Nabarro potential, are constructed numerically, starting from the anticontinuum limit. The solitons with the amplitude exceeding a certain critical value suffer an instability leading to blowup, which is a specific feature of the nonlinear parity-time-symmetric chain, making it dynamically different from DNLS lattices. A qualitative explanation of this feature is proposed. The instability threshold drops with the increase of the gain-loss coefficient, but it does not depend on the lattice coupling constant, nor on the soliton's velocity.

101 citations

Journal ArticleDOI
TL;DR: Novel classes of optical vector solitons that consist of incoherently coupled self-trapped "necklace" beams carrying zero, integer, and even fractional angular momentum are introduced.
Abstract: We introduce novel classes of optical vector solitons that consist of incoherently coupled self-trapped ''necklace'' beams carrying zero, integer, and even fractional angular momentum. Because of the stabilizing mutual attraction between the components, such stationary localized structures exhibit quasistable propagation for much larger distances than the corresponding scalar vortex solitons and expanding scalar necklace beams.

100 citations

Journal ArticleDOI
TL;DR: In this paper, the authors analyzed the first examples of oscillatory instabilities of dark solitons, by considering the important cases of the discrete nonlinear Schrodinger ( DNLS) and generalized Ablowitz-Ladik (AL-DNLS) models.
Abstract: Wave instabilities are probably the most remarkable nonlinear phenomena that may occur in nature [1]. One of the first instabilities discovered for nonlinear models was the modulational instability, which is known to be an effective physical mechanism in fluids [2] and optics [3] for breakup of continuous modes into solitary waves. Also, the solitary waves themselves may become unstable, and the analysis of their instabilities is an important problem of nonlinear physics. Instabilities are known to occur for both bright [4] and dark [5] solitary waves of different nonintegrable nonlinear models. Recently, a new type of solitary-wave instability, oscillatory instability, has been found to occur for bright Bragg gap solitons in the generalized Thirring model [6]. Such an instability is characterized by complex eigenvalues, and its scenario is associated with a resonance between the long-wavelength radiation and soliton internal modes which appear in the soliton spectrum when the model becomes nonintegrable [7]. In spite of the fact that oscillatory instabilities appear often in dissipative models [8], their manifestation in continuous Hamiltonian models is rare [9], and so far no example has been known for oscillatory instability of dark solitons. The aim of this Letter is twofold. First, we analyze what we believe to be the first examples of oscillatory instabilities of dark solitons, by considering the important cases of the discrete nonlinear Schrodinger ( DNLS) and generalized Ablowitz-Ladik (AL-DNLS) models. We reveal two different scenarios for the dark-soliton oscillatory instability, which may occur due to either a resonance between radiation modes and the soliton internal mode, or a resonance between two soliton internal modes. Second, we demonstrate that even a weak inherent discreteness may drastically modify the dynamics of a nonlinear system leading to instabilities which have no analog in the continuum limit. First, we consider the well-known DNLS equation, i Ÿ

99 citations


Cited by
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08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

01 May 1993
TL;DR: Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems.
Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

29,323 citations

28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations