Search results for "Quantum electrodynamics."
showing 10 items of 797 documents
Experience Europe! The Reception of the Leuenberger Agreement as Model and Constant Challenge
2016
Abstract The Leuenberg Agreement (LA) is one of the most productive ecumenical documents ever seen. It initiated a church fellowship, the “Community of Protestant Churches in Europe” (CPCE). LA evoked an ongoing process of its’ own reception that can be seen in a variety of different expressions such as church communion, doctrinal conversations and public statements. However, this reception is still all too frequent limited to the European level of interaction between the member churches of CPCE. It remains one of the main challenges for the Community, a condition for “Verbindlichkeit” and the legitimated representation of its members to strengthen the awareness for the relevance of LA and …
Optical Dark Rogue Wave
2016
AbstractPhotonics enables to develop simple lab experiments that mimic water rogue wave generation phenomena, as well as relativistic gravitational effects such as event horizons, gravitational lensing and Hawking radiation. The basis for analog gravity experiments is light propagation through an effective moving medium obtained via the nonlinear response of the material. So far, analogue gravity kinematics was reproduced in scalar optical wave propagation test models. Multimode and spatiotemporal nonlinear interactions exhibit a rich spectrum of excitations, which may substantially expand the range of rogue wave phenomena and lead to novel space-time analogies, for example with multi-parti…
Extraction of Singlet States from Noninteracting High-Dimensional Spins
2008
We present a scheme for the extraction of singlet states of two remote particles of arbitrary quantum spin number. The goal is achieved through post-selection of the state of interaction mediators sent in succession. A small number of iterations is sufficient to make the scheme effective. We propose two suitable experimental setups where the protocol can be implemented.
Stability of hydrodynamical relativistic planar jets
2004
The effects of relativistic dynamics and thermodynamics in the development of Kelvin-Helmholtz instabilities in planar, relativistic jets along the early phases (namely linear and saturation phases) of evolution has been studied by a combination of linear stability analysis and high-resolution numerical simulations for the most unstable first reflection modes in the temporal approach. Three different values of the jet Lorentz factor (5, 10 and 20) and a few different values of specific internal energy of the jet matter (from 0.08 to $60.0 c^2$) have been considered. Figures illustrating the evolution of the perturbations are also shown.
Strongly interacting Fermi gases with density imbalance
2005
We consider density-imbalanced Fermi gases of atoms in the strongly interacting, i.e. unitarity, regime. The Bogoliubov-deGennes equations for a trapped superfluid are solved. They take into account the finite size of the system, as well as give rise to both phase separation and FFLO type oscillations in the order parameter. We show how radio-frequency spectroscopy reflects the phase separation, and can provide direct evidence of the FFLO-type oscillations via observing the nodes of the order parameter.
Time-dependent transport in Aharonov–Bohm interferometers
2010
A numerical approach is employed to explain transport characteristics in realistic, quantum Hall based Aharonov-Bohm interferometers. First, the spatial distribution of incompressible strips, and thus the current channels, are obtained applying a self-consistent Thomas-Fermi method to a realistic heterostructure under quantized Hall conditions. Second, the time-dependent Schr\"odinger equation is solved for electrons injected in the current channels. Distinctive Aharonov-Bohm oscillations are found as a function of the magnetic flux. The oscillation amplitude strongly depends on the mutual distance between the transport channels and on their width. At an optimal distance the amplitude and t…
Depletion in Bose-Einstein condensates using quantum field theory in curved space
2007
5 pages.-- PACS nrs.: 03.75.Kk; 05.30.Jp; 04.62.+v; 04.70.Dy.-- ISI Article Identifier: 000246074600122.-- ArXiv pre-print available at: http://arxiv.org/abs/cond-mat/0610367
Cold-Atom-Induced Control of an Optomechanical Device
2010
We consider a cavity with a vibrating end mirror and coupled to a Bose-Einstein condensate. The cavity field mediates the interplay between mirror and collective oscillations of the atomic density. We study the implications of this dynamics and the possibility of an indirect diagnostic. Our predictions can be observed in a realistic setup that is central to the current quest for mesoscopic quantumness.
Dissipative solitons for mode-locked lasers
2012
International audience; Dissipative solitons are localized formations of an electromagnetic field that are balanced through an energy exchange with the environment in presence of nonlinearity, dispersion and/or diffraction. Their growing use in the area of passively mode-locked lasers is remarkable: the concept of a dissipative soliton provides an excellent framework for understanding complex pulse dynamics and stimulates innovative cavity designs. Reciprocally, the field of mode-locked lasers serves as an ideal playground for testing the concept of dissipative solitons and revealing their unusual dynamics. This Review provides basic definitions of dissipative solitons, summarizes their imp…
Shell structure and the fluctuation of the nuclear density distribution
1984
We investigate the relation between the density-fluctuations in nuclei and their description by single-particle models, i.e. the shell model and the Hartree-Fock method; the question is whether every shell-structure necessarily leads to those fluctuations. We demonstrate the flexibility of the single-particle models by constructing a shell-model potential and an effective Hartree-Fock potential, respectively, which produce completely flat distributions without any density fluctuation; this means that “shell structure” is not sufficient an explanation for the fluctuations. Only the additional requirement that the dynamical features of nuclei are also met selects a subclass of “reasonable” po…