ALBERT

Description: Author(s): M. Sato, T. Mukaide, T. Nakaguchi, and A. J. Sievers The experimental properties of intrinsic localized modes (ILMs) have long been compared with theoretical dynamical lattice models that make use of nonlinear onsite and/or nearest-neighbor intersite potentials. Here it is shown for a one-dimensional lumped electrical transmission line that a nonlinea… [Phys. Rev. E 94, 012223] Published Mon Jul 25, 2016

Description: Author(s): A. J. Sievers, M. Sato, J. B. Page, and T. Rössler The possibility of thermal excitation of intrinsic localized modes (ILMs) arising from anharmonicity in ionic perfect crystals is studied numerically for realistic model systems in one and three dimensions. Implications are discussed for an interesting high-temperature feature seen in earlier inelas... [Phys. Rev. B 88, 104305] Published Thu Sep 19, 2013

Description: It is well known that a moving intrinsic localized mode (ILM) in a nonlinear physical lattice looses energy because of the resonance between it and the underlying small amplitude plane wave spectrum. By exploring the Fourier transform (FT) properties of the nonlinear force of a running ILM in a driven and damped 1D nonlinear lattice, as described by a 2D wavenumber and frequency map, we quantify the magnitude of the resonance where the small amplitude normal mode dispersion curve and the FT amplitude components of the ILM intersect. We show that for a traveling ILM characterized by a specific frequency and wavenumber, either inside or outside the plane wave spectrum, and for situations where both onsite and intersite nonlinearity occur, either of the hard or soft type, the strength of this resonance depends on the specific mix of the two nonlinearities. Examples are presented demonstrating that by engineering this mix the resonance can be greatly reduced. The end result is a supertransmission channel for either a driven or undriven ILM in a nonintegrable, nonlinear yet physical lattice.

Description: Author(s): M. Sato, S. Imai, N. Fujita, W. Shi, Y. Takao, Y. Sada, B. E. Hubbard, B. Ilic, and A. J. Sievers An intrinsic localized mode (ILM) represents a localized vibrational excitation in a nonlinear lattice. Such a mode will stay in resonance as the driver frequency is changed adiabatically until a bifurcation point is reached, at which point the ILM switches and disappears. The dynamics behind switch... [Phys. Rev. E 87, 012920] Published Thu Jan 31, 2013

Description: Author(s): M. Sato, S. Imai, N. Fujita, S. Nishimura, Y. Takao, Y. Sada, B. E. Hubbard, B. Ilic, and A. J. Sievers [Phys. Rev. Lett. 107, 234101] Published Wed Nov 30, 2011

Description: Author(s): L. Q. English, F. Palmero, P. Candiani, J. Cuevas, R. Carretero-González, P. G. Kevrekidis, and A. J. Sievers We show experimentally and numerically that an intrinsic localized mode (ILM) can be stably produced (and experimentally observed) via subharmonic, spatially homogeneous driving in the context of a nonlinear electrical lattice. The precise nonlinear spatial response of the system has been seen to de... [Phys. Rev. Lett. 108, 084101] Published Wed Feb 22, 2012

Description: Author(s): M. Haas, V. Hizhnyakov, A. Shelkan, M. Klopov, and A. J. Sievers [Phys. Rev. B 84, 144303] Published Thu Oct 13, 2011

Description: Both low frequency and high frequency impurity modes have been produced in a SiN micromechanical cantilever array by illumination with either an infrared or visible laser. When such laser-induced impurities are placed near a driven intrinsic localized mode (ILM), it is either repelled or attracted. By measuring the linear response spectrum for these two cases, it was found that vibrational hopping of the ILM takes place when the natural frequency of the ILM and an intrinsic even symmetry linear local mode are symmetrically located about the driven ILM frequency so that parametric excitation of these two linear modes is enhanced, amplifying the lateral motion of the ILM. Numerical simulations are consistent with these signature findings. It is also demonstrated that the correct sign of the observed interaction can be found with a harmonic lattice-impurity model but the magnitude of the effect is enhanced in a nonlinear lattice.

Description: Fast radio bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate is comparable to the core-collapse supernova rate out to redshift 0.5. If the observed dispersion measures are assumed to be dominated by the intergalactic medium, the sources are at cosmological distances with redshifts of 0.2 to 1 (refs 10 and 11). These parameters are consistent with a wide range of source models. One fast burst revealed circular polarization of the radio emission, but no linear polarization was detected, and hence no Faraday rotation measure could be determined. Here we report the examination of archival data revealing Faraday rotation in the fast radio burst FRB 110523. Its radio flux and dispersion measure are consistent with values from previously reported bursts and, accounting for a Galactic contribution to the dispersion and using a model of intergalactic electron density, we place the source at a maximum redshift of 0.5. The burst has a much higher rotation measure than expected for this line of sight through the Milky Way and the intergalactic medium, indicating magnetization in the vicinity of the source itself or within a host galaxy. The pulse was scattered by two distinct plasma screens during propagation, which requires either a dense nebula associated with the source or a location within the central region of its host galaxy. The detection in this instance of magnetization and scattering that are both local to the source favours models involving young stellar populations such as magnetars over models involving the mergers of older neutron stars, which are more likely to be located in low-density regions of the host galaxy.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Masui, Kiyoshi -- Lin, Hsiu-Hsien -- Sievers, Jonathan -- Anderson, Christopher J -- Chang, Tzu-Ching -- Chen, Xuelei -- Ganguly, Apratim -- Jarvis, Miranda -- Kuo, Cheng-Yu -- Li, Yi-Chao -- Liao, Yu-Wei -- McLaughlin, Maura -- Pen, Ue-Li -- Peterson, Jeffrey B -- Roman, Alexander -- Timbie, Peter T -- Voytek, Tabitha -- Yadav, Jaswant K -- England -- Nature. 2015 Dec 24;528(7583):523-5. doi: 10.1038/nature15769. Epub 2015 Dec 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z1, Canada. ; Canadian Institute for Advanced Research, CIFAR Program in Cosmology and Gravity, Toronto, Ontario M5G 1Z8, Canada. ; McWilliams Center for Cosmology, Carnegie Mellon University, Department of Physics, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, USA. ; Astrophysics and Cosmology Research Unit, School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4001, South Africa. ; National Institute for Theoretical Physics (NITheP), KZN node, Durban 4001, South Africa. ; Department of Physics, University of Wisconsin, Madison, Wisconsin 53706-1390, USA. ; Academia Sinica Institute of Astronomy and Astrophysics, 11F Astro-Math Building, AS/NTU 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan. ; National Astronomical Observatories, Chinese Academy of Science, 20A Datun Road, Beijing 100012, China. ; Center of High Energy Physics, Peking University, Beijing 100871, China. ; Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics, and Computer Science, University of KwaZulu-Natal, Durban 4001, South Africa. ; Department of Astronomy and Astrophysics, University of Toronto, 50 St George Street, Toronto, Ontario M5S 3H4, Canada. ; Department of Physics, National Sun Yat-Sen University No. 70, Lianhai Road, Gushan District, Kaohsiung City 804, Taiwan. ; Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA. ; Canadian Institute for Theoretical Astrophysics, 60 St George Street, Toronto, Ontario M5S 3H8, Canada. ; Perimeter Institute, 31 Caroline Street, Waterloo N2L 2Y5, Canada. ; Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, PO 140306, India.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26633633" target="_blank"〉PubMed〈/a〉