388 research outputs found
Anharmonicity and its significance to non-Ohmic electric conduction
We provide here a thorough analysis of the interplay between anharmonic lattice dynamics (with exponential repulsion between units) and electric conduction in a driven-dissipative electrically charged one-dimensional system. First, we delineate the ranges of parameter values where, respectively, subsonic and supersonic wave solitons are possible along the lattice. Then, we study the consequences of the soliton-mediated coupling of light negative to heavy positive charges (lattice units). In the presence of an external electric field we obtain the current-field characteristics for a wide range of values of all parameters defining the system. Finally, we discuss the conditions for an Ohmic-non-Ohmic transition of the electric current as the electric field strength is varied
Dissipative Chaos in Semiconductor Superlattices
We consider the motion of ballistic electrons in a miniband of a
semiconductor superlattice (SSL) under the influence of an external,
time-periodic electric field. We use the semi-classical balance-equation
approach which incorporates elastic and inelastic scattering (as dissipation)
and the self-consistent field generated by the electron motion. The coupling of
electrons in the miniband to the self-consistent field produces a cooperative
nonlinear oscillatory mode which, when interacting with the oscillatory
external field and the intrinsic Bloch-type oscillatory mode, can lead to
complicated dynamics, including dissipative chaos. For a range of values of the
dissipation parameters we determine the regions in the amplitude-frequency
plane of the external field in which chaos can occur. Our results suggest that
for terahertz external fields of the amplitudes achieved by present-day free
electron lasers, chaos may be observable in SSLs. We clarify the nature of this
novel nonlinear dynamics in the superlattice-external field system by exploring
analogies to the Dicke model of an ensemble of two-level atoms coupled with a
resonant cavity field and to Josephson junctions.Comment: 33 pages, 8 figure
Hydrodynamics
The phenomena related to the flow of fluids are generally complex, and difficult to quantify. New approaches - considering points of view still not explored - may introduce useful tools in the study of Hydrodynamics and the related transport phenomena. The details of the flows and the properties of the fluids must be considered on a very small scale perspective. Consequently, new concepts and tools are generated to better describe the fluids and their properties. This volume presents conclusions about advanced topics of calculated and observed flows. It contains eighteen chapters, organized in five sections: 1) Mathematical Models in Fluid Mechanics, 2) Biological Applications and Biohydrodynamics, 3) Detailed Experimental Analyses of Fluids and Flows, 4) Radiation-, Electro-, Magnetohydrodynamics, and Magnetorheology, 5) Special Topics on Simulations and Experimental Data. These chapters present new points of view about methods and tools used in Hydrodynamics
Nonlinear pseudospin dynamics of exciton polaritons in semiconductor microcavity
Semiconductor microcavities offer the possibility to enhance the interaction between cavity photons and elementary excitations of the semiconductor. The excitations considered here are excitons, bound states of electrons and holes. The coherent interaction between these excitons and photons leads to the formation of quasiparticles called exciton-polaritons. The respective interaction regime is termed strong coupling regime. Exciton-polaritons inherit properties from both their photonic and their electronic component. A typical property inherited from the excitons is the spin.
The scope of this thesis is twofold. On the one hand, the general properties of exciton-polaritons are studied theoretically. On the other hand, the influence of the exciton spin is analyzed. Several effects and tools known from nonlinear dynamics such as pattern formation, cavity solitons, domain walls, perturbation theory, and bifurcation theory are used in order to highlight these properties.
The findings of this thesis expand the knowledge about the theoretical foundations of polariton physics. This may pave the way to potential application of semiconductor microcavities as all-optical information processing and storage devices
Quodons in Mica 2013
Quodons in Mica 2013
INDEX
1. Introduction.
3. JFR Archilla, SMM Coelho, FD Auret, V Dubinko and V Hizhnyakov.
Experimental observation of moving discrete breathers in germanium.
5. L Brzihik.
Bisolectrons in harmonic and anharmonic lattices.
6. AP Chetverikov.
Solitons and charge transport in triangular and quadratic Morse lattices.
7. LA Cisneros-Ake.
Travelling coherent structures in the electron transport in 2D anharmonic crystal lattices.
8. SMM Coelho, FD Auret, JM Nel and JFR Archilla.
The origin of defects induced in ultra-pure germanium by Electron Beam Deposition.
10. S Comorosan and M Apostol.
Theory vs. Reality - Localized excitations induced by optical manipulation of proteins,
as a different approach to link experiments with theory.
12. L Cruzeiro.
The amide I band of crystalline acetanilide: old data under new light.
13. SV Dmitriev and AA Kistanov.
Moving discrete breathers in crystals with NaCl structure.
15. V Dubinko, JFR Archilla, SMM Coelho and V Hizhnyakov.
Modeling of the annealing of radiation-induced defects in germanium by moving discrete breathers.
16. JC Eilbeck.
Numerical simulations of nonlinear modes in mica: past, present and future.
17. A Ferrando, C Mili\'an, DE Ceballos-Herrera and Dmitry V. Skryabin.
Soliplasmon resonances at metal-dielectric interfaces.
19. YuB Gaididei.
Energy localization in nonlinear systems with flexible geometry.
20. D Hennig.
Existence and non-existence of breather solutions in damped and driven nonlinear lattices.
21. P Jason and M Johansson.
Existence, dynamics and mobility of Quantum Compactons in an extended Bose-Hubbard model.
22. N.
Jiménez, JFR Archilla, Y. Kosevich, V. Sánchez-Morcillo and LM García-Raffi.
A crowdion in mica. Between K40 recoil and transmission sputtering.
24. M Johansson.
Strongly localized moving discrete solitons (breathers): new ways to beat the Peierls-Nabarro barrier.
26. YA Kosevich and AV Savin. Energy transport in molecular chains with combined anharmonic potentials of pair interatomic interaction.
28. B Malomed, C Mejía-Cortés and RA Vicencio.
Mobile discrete solitons in the one-dimensional lattice with the cubic-quintic nonlinearity.
29. FM Russell.
Recording process in iron-rich muscovite crystals.
30. L Salasnich.
Bright solitons of attractive Bose-Einstein condensates confined in quasi-1D optical lattice.
31. V Sánchez-Morcillo, LM, Garcíaa-Raffi, V. Romero-Garcíaa, R. Picó, A. Cebrecos, and Kestutis Staliunas.
Wave localization in chirped sonic crystals.
32. P Selyschev, V Sugakov and T Didenko.
Peculiarities of the change of temperature and heat transfer under irradiation.
33. K Staliunas.
Taming of Modulation Instability: Manipulation, and Complete Suppression of Instability by Spatio-Temporal Periodic Modulation.
34. G Tsironis.
Gain-Driven Breathers in PT-Symmetric Metamaterials.
36. JAD Wattis and IA Butt.
Moving breather modes in two-dimensional lattices.Ministerio de Ciencia e Innovación FIS2008-0484
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