Generating and Observing Soliton Dynamics in Bose Einstein Condensates
Author : Paul Benjamin Wigley
Publisher :
Page : 0 pages
File Size : 10,41 MB
Release : 2017
Category :
ISBN :
Author : Paul Benjamin Wigley
Publisher :
Page : 0 pages
File Size : 10,41 MB
Release : 2017
Category :
ISBN :
Author : Panayotis G. Kevrekidis
Publisher : Springer Science & Business Media
Page : 398 pages
File Size : 25,65 MB
Release : 2007-12-29
Category : Science
ISBN : 3540735917
This book, written by experts in the fields of atomic physics and nonlinear science, covers the important developments in a special aspect of Bose-Einstein condensation, namely nonlinear phenomena in condensates. Topics covered include bright, dark, gap and multidimensional solitons; vortices; vortex lattices; optical lattices; multicomponent condensates; mathematical methods/rigorous results; and the beyond-the-mean-field approach.
Author : Russell Campbell
Publisher :
Page : 0 pages
File Size : 29,18 MB
Release : 2018
Category :
ISBN :
The properties of Bose-Einstein condensates can be studied and controlled effectively when trapped in optical lattices formed by two counter-propagating laser beams. The dynamics of Bose-Einstein condensates in optical lattices are well-described by a continuous model using the Gross-Pitaevskii equation in a modulated potential or, in the case of deep potentials, a discrete model using the Discrete Nonlinear Schrodinger equation. Spatially localised modes, known as lattice solitons in the continuous model, or discrete breathers in the discrete model, can occur and are the focus of this thesis. Theoretical and computational studies of these localised modes are investigated in three different situations. Firstly, a model of a Bose-Einstein condensate in a ring optical lattice with atomic dissipations applied at a stationary or at a moving location on the ring is presented in the continuous model. The localised dissipation is shown to generate and stabilise both stationary and traveling lattice solitons. The solutions generated include spatially stationary quasiperiodic lattice solitons and a family of traveling lattice solitons with two intensity peaks per potential well with no counterpart in the discrete case. Collisions between traveling and stationary lattice solitons as well as between two traveling lattice solitons display a dependence on the lattice depth. Then, collisions with a potential barrier of either travelling lattice solitons or travelling discrete breathers are investigated along with their dependence on the height of the barrier. Regions of complete reection or of partial reflection where the incoming soliton/breather is split in two, are observed and understood interms of the soliton properties. Partial trapping of the atoms in the barrier is observed for positive barrier heights due to the negative effective mass of the solitons/breathers. Finally, two coupled discrete nonlinear Schrodinger equations can describe the interaction and collisions of breathers in two-species Bose-Einstein condensates in deep optical lattices. This is done for two cases of experimental relevance: a mixture of two ytterbium isotopes and a mixture of Rubidium (87Rb) and Potassium(41K) atoms. Depending on their initial separation, interaction between stationary breathers of different species can lead to the formation of symbiotic localised structures or transform one of the breathers from a stationary one into a travelling one. Collisions between travelling and stationary discrete breathers composed of different species are separated in four distinct regimes ranging from totally elastic when the interspecies interaction is highly attractive to mutual destruction when the interaction is suffciently large and repulsive.
Author : Pisin Chen
Publisher : World Scientific
Page : 658 pages
File Size : 24,14 MB
Release : 2002
Category : Science
ISBN : 9810249500
This proceedings volume records the advances in quantum beam physics since the first meeting in Monterey (1998). In addition to further progress regarding quantum effects in beam dynamics, photon-electron interaction in beam handling, beam phenomena under strong fields, and quantum methodologies in beam physics, the newly introduced topics ? the physics of condensed beams as well as astro-beam physics and laboratory astrophysics ? have also been well documented by world experts in the field.This book should be a valuable reference to those who are interested in the joint frontiers of beam physics and other fields such as astrophysics and condensed matter physics.
Author : Dong Yan
Publisher :
Page : 133 pages
File Size : 43,55 MB
Release : 2014
Category : Bose-Einstein condensation
ISBN :
This dissertation focuses on the properties of nonlinear waves in Bose-Einstein condensates (BECs). The fundamental model here is the nonlinear Schrodinger equation, the so-called Gross-Pitaevskii (GP) equation, which is a mean-field description of BECs. The systematic analysis begins by considering the dark-bright (DB)-soliton interactions and multiple-dark-bright-soliton complexes in atomic two-component BECs. The interaction between two DB solitons in a homogeneous condensate and at the presence of the trap are both considered. Our analytical approximation relies in a Hamiltonian perturbation theory, which leads to an equation of motion of the centers of DB-soliton interacting pairs. Employing this equation, we demonstrate the existence of robust DB-soliton molecules, in the form of stationary two- and three-DB-soliton states. Also the equilibrium distance of the constituent solitons and the corresponding oscillation frequencies are found semianalytically, where the latter corresponds to the characteristic anomalous modes' eigenfrequencies that we numerically computed via a so called Bogoliubov-de Gennes (BdG) linearization analysis. Those studies are discussed in Chapter 2. Then, we extend our studies to the dynamics of dark-bright (DB) solitons in binary BECs at finite temperature using a system of two-coupled dissipative GPs. We show that the effect of the bright soliton is to partially stabilize dark solitons against temperature-induced dissipation, thus providing longer lifetimes in Chapter 3. Furthermore, the dark-dark (DD) solitons as a prototypical coherent structure that emerges in two-component BECs are studied and are connected to dark-bright (DB) solitons via SO(2) rotation. We obtained their beating frequency and their frequency of oscillation inside a parabolic trap. They are identified as exact periodic orbits in the Manakov limit of equal inter- and intra- species nonlinearity strengths with and without the trap and we showcase the persistence of such states upon weak deviations from this limit. Also we investigated in detail the effect of the deviation from the Manakov case by considering different from unity scattering length ratios in Chapter 4. Next, we revisited Hamiltonian eigenvalue problems that typically arise in the linearization around a stationary state of a Hamiltonian nonlinear PDE. Also we presented a overview of the known facts for the eigenvalue counts of the corresponding unstable spectra. In particular, we focused on a straightforward plan to implement finite-dimensional techniques for locating this spectrum via the singular points of the meromorphic Krein Matrix and illustrated the value of the approach by considering realistic problems for recently observed experimentally multivortex and multisoliton solutions in atomic Bose-Einstein condensates in Chapter 5. In the two dimensional scenario, we also examine the stability and dynamics of vortices under the effect of dissipation used as a simplified model for the inclusion of the effect of finite temperatures in atomic BECs, which enables an analytical prediction that can be compared directly to numerical results in Chapter 6. In all the above studies, our analytical prediction from the equation of motion are in good agreement with the numerical results from the BdG analysis.
Author : JiaJia Chang
Publisher :
Page : pages
File Size : 11,61 MB
Release : 2013
Category :
ISBN : 9781303465208
Several prototypical experiments concerning quantum hydrodynamics are realized in this thesis using one and two-component Bose-Einstein condensates (BECs). The experiments are conducted with an experimental apparatus built at WSU that is capable of reliably producing 87Rb BECs and 40K degenerate Fermi gases (DFGs). The apparatus, which has undergone many modifications and upgrades since it was first built, will be described in detail. The upgrades include the addition of fermionic potassium atoms, installation of a fully electromagnetic Ioffe-Pritchard type trap with excellent optical access to the BEC, and the addition of an optical dipole trap (and optical lattices).
Author : Wiesław Leoński
Publisher : MDPI
Page : 104 pages
File Size : 33,62 MB
Release : 2020-06-03
Category : Mathematics
ISBN : 3039288008
Recent research in the fields related to the quantum information theory (QIT) is becoming some of the most intriguing and promising investigations in contemporary physics. Many novel QIT concepts are discussed in the literature, and the broad range of new models of quantum optics and solid-state physics have been recently considered in the context of QIT. Theideas of symmetry are widely discussed in all physical sciences, becoming keystones of various concepts and considerations, leading to novel discoveries in physics. Thus, this Special Issue is devoted to the broad range of QIT topics that are related to the ideas of symmetry. It covers a broad range of ideas that can develop upon the basic research and applications in the field of quantum information, and in general, quantum theory.
Author : Andreas Weller
Publisher :
Page : 120 pages
File Size : 32,64 MB
Release : 2009
Category :
ISBN :
Author : L. V. Chen
Publisher : Nova Publishers
Page : 294 pages
File Size : 41,73 MB
Release : 2006
Category : Science
ISBN : 9781594545597
Since their discovery a mere thirty years ago, solitons have been invoked to explain such diverse phenomena as: The long lived 'giant red spot' in the highly turbulent Jovian atmosphere. The famous Fermi-Pasta-Ulam paradox wherein a nonlinearly coupled lattice of particles does not display the expected equipartition of energy among available modes: ion-acoustic waves in a plasma; energy storage and transfer in proteins via the Davydov soliton; and, the propagation of short laser pulses in optical fibres over long distances with negligible shape change. This volume presents important research from around the globe.
Author : Panayotis G. Kevrekidis
Publisher : SIAM
Page : 437 pages
File Size : 44,42 MB
Release : 2015-08-04
Category : Mathematics
ISBN : 1611973937
Bose?Einstein condensation is a phase transition in which a fraction of particles of a boson gas condenses into the same quantum state known as the Bose?Einstein condensate (BEC). The aim of this book is to present a wide array of findings in the realm of BECs and on the nonlinear Schr?dinger-type models that arise therein. The Defocusing Nonlinear Schr?dinger Equation is a broad study of nonlinear excitations in self-defocusing nonlinear media. It summarizes state-of-the-art knowledge on the defocusing nonlinear Schr?dinger-type models in a single volume and contains a wealth of resources, including over 800 references to relevant articles and monographs and a meticulous index for ease of navigation.