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Full-Text Articles in Physical Sciences and Mathematics
A Mean-Field Analogue Of The Hong-Ou-Mandel Experiment With Bright Solitons, Zhi-Yuan Sun, Panos Kevrekidis, Peter Kruger
A Mean-Field Analogue Of The Hong-Ou-Mandel Experiment With Bright Solitons, Zhi-Yuan Sun, Panos Kevrekidis, Peter Kruger
Panos Kevrekidis
In the present work, we theoretically propose and numerically illustrate a mean-field analog of the Hong-Ou-Mandel experiment with bright solitons. More specifically, we scatter two solitons off of each other (in our setup, the bright solitons play the role of a classical analog to the quantum photons of the original experiment), while the role of the beam splitter is played by a repulsive Gaussian barrier. In our classical scenario, distinguishability of the particles yields, as expected, a 0.5 split mass on either side. Nevertheless, for very slight deviations from the completely symmetric scenario, a near-perfect transmission can be constructed instead, …
A Tale Of Two Distributions: From Few To Many Vortices In Quasi-Two-Dimensional Bose-Einstein Condensates, T. Kolokolnikov, Panos Kevrekidis, R. Carretero-Gonzalez
A Tale Of Two Distributions: From Few To Many Vortices In Quasi-Two-Dimensional Bose-Einstein Condensates, T. Kolokolnikov, Panos Kevrekidis, R. Carretero-Gonzalez
Panos Kevrekidis
Motivated by the recent successes of particle models in capturing the precession and interactions of vortex structures in quasi-two-dimensional Bose–Einstein condensates, we revisit the relevant systems of ordinary differential equations. We consider the number of vortices N as a parameter and explore the prototypical configurations (‘ground states’) that arise in the case of few or many vortices. In the case of few vortices, we modify the classical result illustrating that vortex polygons in the form of a ring are unstable for N≥7. Additionally, we reconcile this modification with the recent identification of symmetry-breaking bifurcations for the cases of N=2,…,5. We …
Dynamic And Energetic Stabilization Of Persistent Currents In Bose-Einstein Condensates, K.J. H. Law, T. W. Neely, Panos Kevrekidis, B. P. Anderson, A. S. Bradley, R. Carretero-Gonzalez
Dynamic And Energetic Stabilization Of Persistent Currents In Bose-Einstein Condensates, K.J. H. Law, T. W. Neely, Panos Kevrekidis, B. P. Anderson, A. S. Bradley, R. Carretero-Gonzalez
Panos Kevrekidis
We study conditions under which vortices in a highly oblate harmonically trapped Bose-Einstein condensate (BEC) can be stabilized due to pinning by a blue-detuned Gaussian laser beam, with particular emphasis on the potentially destabilizing effects of laser beam positioning within the BEC. Our approach involves theoretical and numerical exploration of dynamically and energetically stable pinning of vortices with winding number up to S=6, in correspondence with experimental observations. Stable pinning is quantified theoretically via Bogoliubov-de Gennes excitation spectrum computations and confirmed via direct numerical simulations for a range of conditions similar to those of experimental observations. The theoretical and numerical …
Exploring Vortex Dynamics In The Presence Of Dissipation: Analytical And Numerical Results, D. Yan, R. Carretero-Gonzalez, D. J. Frantzeskakis, Panos Kevrekidis, N. P. Proukakis, D. Spirn
Exploring Vortex Dynamics In The Presence Of Dissipation: Analytical And Numerical Results, D. Yan, R. Carretero-Gonzalez, D. J. Frantzeskakis, Panos Kevrekidis, N. P. Proukakis, D. Spirn
Panos Kevrekidis
In this paper, we examine the dynamical properties of vortices in atomic Bose-Einstein condensates in the presence of phenomenological dissipation, used as a basic model for the effect of finite temperatures. In the context of this so-called dissipative Gross-Pitaevskii model, we derive analytical results for the motion of single vortices and, importantly, for vortex dipoles, which have become very relevant experimentally. Our analytical results are shown to compare favorably to the full numerical solution of the dissipative Gross-Pitaevskii equation where appropriate. We also present results on the stability of vortices and vortex dipoles, revealing good agreement between numerical and analytical …
Scattering And Leapfrogging Of Vortex Rings In A Superfluid, R. M. Caplan, J. D. Talley, R. Carretero-Gonzalez, Panos Kevrekidis
Scattering And Leapfrogging Of Vortex Rings In A Superfluid, R. M. Caplan, J. D. Talley, R. Carretero-Gonzalez, Panos Kevrekidis
Panos Kevrekidis
The dynamics of vortex ring pairs in the homogeneous nonlinear Schrödinger equation is studied. The generation of numerically exact solutions of traveling vortex rings is described and their translational velocity compared to revised analytic approximations. The scattering behavior of co-axial vortex rings with opposite charge undergoing collision is numerically investigated for different scattering angles yielding a surprisingly simple result for its dependence as a function of the initial vortex ring parameters. We also study the leapfrogging behavior of co-axial rings with equal charge and compare it with the dynamics stemming from a modified version of the reduced equations of motion …
From Nodeless States And Vortices To Gray Rings And Symmetry-Broken States In Two-Dimensional Polariton Condensates, A. S. Rodrigues, Panos Kevrekidis, R. Carretero-Gonzalez, J. Cuevas, D. J. Frantzeskakis, F. Palermo
From Nodeless States And Vortices To Gray Rings And Symmetry-Broken States In Two-Dimensional Polariton Condensates, A. S. Rodrigues, Panos Kevrekidis, R. Carretero-Gonzalez, J. Cuevas, D. J. Frantzeskakis, F. Palermo
Panos Kevrekidis
We consider the existence, stability and dynamics of the nodeless state and fundamental nonlinear excitations, such as vortices, for a quasi-two-dimensional polariton condensate in the presence of pumping and nonlinear damping. We find a series of interesting features that can be directly contrasted to the case of the typically energy-conserving ultracold alkali-atom Bose–Einstein condensates (BECs). For sizeable parameter ranges, in line with earlier findings, the nodeless state becomes unstable towards the formation of stable nonlinear single or multi-vortex excitations. The potential instability of the single vortex is also examined and is found to possess similar characteristics to those of the …
Beating Dark-Dark Solitons And Zitterbewegung In Spin-Orbit Coupled Bose-Einstein Condensates, V. Achilleos, D. J. Frantzeskakis, Panos Kevrekidis
Beating Dark-Dark Solitons And Zitterbewegung In Spin-Orbit Coupled Bose-Einstein Condensates, V. Achilleos, D. J. Frantzeskakis, Panos Kevrekidis
Panos Kevrekidis
We present families of beating dark-dark solitons in spin-orbit (SO) -coupled Bose-Einstein condensates. These families consist of solitons residing simultaneously in the two bands of the energy spectrum. The soliton components are characterized by two different spatial and temporal scales, which are identified by a multiscale expansion method. The solitons are “beating” ones, as they perform density oscillations. The characteristic frequency of the latter is relevant to Zitterbewegung (ZB) oscillations, which were recently observed in experiments with SO-coupled condensates [C. Qu et al., Phys. Rev. A 88, 021604(R) (2013); L. J. LeBlanc et al., New J. Phys. 15, 073011 (2013)]. …