Search results for "tangle"
showing 10 items of 420 documents
Continuous-Variable Quantum Teleportation of Discrete-Variable Entanglement
2013
We experimentally demonstrate continuous-variable quantum teleportation of discrete-variable entanglement in the form of a split single photon. Entanglement is optimally transferred for finite resource squeezing by tuning the teleporter's feedforward gain.
Alternative Vinen equation and its extension to rotating counterflow superfluid turbulence
2007
Two alternative Vinen's evolution equations for the vortex line density L in counterflow superfluid turbulence, are physically admissible and lead to analogous results in steady states. In Phys. Rev. B, 69, 094513 (2004) the most used of them was generalized to counterflow superfluid turbulence in rotating containers. Here, the analogous generalization for the alternative Vinen's equation is proposed. Both generalized Vinen's equations are compared with the experimental results, not only in steady-states but also in some unsteady situations. From this analysis follows that the solutions of the alternative Vinen's equation tend significantly faster to the corresponding final steady state val…
Controlled long-range interactions between Rydberg atoms and ions
2016
We theoretically investigate trapped ions interacting with atoms that are coupled to Rydberg states. The strong polarizabilities of the Rydberg levels increases the interaction strength between atoms and ions by many orders of magnitude, as compared to the case of ground state atoms, and may be mediated over micrometers. We calculate that such interactions can be used to generate entanglement between an atom and the motion or internal state of an ion. Furthermore, the ion could be used as a bus for mediating spin-spin interactions between atomic spins in analogy to much employed techniques in ion trap quantum simulation. The proposed scheme comes with attractive features as it maps the bene…
Anyons and transmutation of statistics via vacuum induced Berry phase
2004
We show that bosonic fields may present anyonic behavior when interacting with a fermion in a Jaynes-Cummings-like model. The proposal is accomplished via the interaction of a two-level system with two quantized modes of a harmonic oscillator; under suitable conditions, the system acquires a fractional geometric phase. A crucial role is played by the entanglement of the system eigenstates, which provides a two-dimensional confinement in the effective evolution of the system, leading to the anyonic behavior. For a particular choice of parameters, we show that it is possible to transmute the statistics of the system continually from fermions to bosons. We also present an experimental proposal…
Quantum state engineering in a cavity by Stark chirped rapid adiabatic passage
2006
We propose a robust scheme to generate single-photon Fock states and atom-photon and atom-atom entanglement in atom-cavity systems. We also present a scheme for quantum networking between two cavity nodes using an atomic channel. The mechanism is based on Stark-chirped rapid adiabatic passage (SCRAP) and half-SCRAP processes in a microwave cavity. The engineering of these states depends on the design of the adiabatic dynamics through the static and dynamic Stark shifts.
Vortex-liquid entanglement inBi2Sr2CaCu2O8+δfilms in the presence of quenched disorder
1998
We have investigated the thermally activated behavior of the in-plane electrical resistivity of ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\mathrm{\ensuremath{\delta}}}$ films for magnetic fields $Bl~{10}^{4}\mathrm{G}$ applied parallel to the $c$ axis. The activation energy in the vortex-liquid state changes suddenly at a crossover field ${B}_{\mathrm{cr}}.$ The anisotropy reduction generated by oxygen annealing leads to the increase of the crossover field. For $Bl{B}_{\mathrm{cr}},$ the activation energy $U$ is weakly magnetic-field dependent. For $Bg{B}_{\mathrm{cr}},$ $U(B,T)\ensuremath{\sim}(1\ensuremath{-}{T/T}_{c0}{)/B}^{1/2},$ which corresponds to an entan…
Entanglement Properties and Phase Diagram of the Two-Orbital Atomic Hubbard Model
2009
We study the two-orbital Hubbard model in the limit of vanishing kinetic energy. The phase diagram in the $V-J$ plane, with $V$ and $J$ denoting the interorbital hybridization and exchange coupling respectively, at half filling is obtained. A singlet(dimer)-triplet transition is found for a critical value of the ratio $V/J.$ The entropy of formation, both in the mode and in the particle picture, presents a jump as the same critical line in conformity with the suggested relation between criticality and entanglement.
Modified Mode Coupling Theory of Glassy Dynamics Generated by Entanglement
2004
Increasing the density in systems with strong excluded volume interactions leads simultaneously to an increase of static correlations and a slowing down of the relaxational dynamics. Mode coupling theory in its present form describes this mechanism, satisfactorily. In contrast, for systems where entanglement is dominant, e.g. infinitely thin hard rods on a lattice, glassy dynamics is not driven by increasing static correlations but by entanglement. We show how mode coupling approximation can be modified such that non-vanishing vertices occur which might account for such pure entanglement effects.
A Non-normal-Mode Marginal State of Convection in a Porous Rectangle
2019
Author's accepted manuscript (postprint). This is a post-peer-review, pre-copyedit version of an article published in Transport in Porous Media. The final authenticated version is available online at: http://dx.doi.org/10.1007/s11242-019-01263-5. The fourth-order Darcy–Bénard eigenvalue problem for onset of thermal convection in a 2D rectangular porous box is investigated. The conventional type of solution has normal-mode dependency in at least one of the two spatial directions. The present eigenfunctions are of non-normal-mode type in both the horizontal and the vertical direction. A numerical solution is found by the finite element method, since no analytical method is known for this non-…
Entangling two spatially separate cavities
2003
A scheme for the transfer of entanglement among systems via successive coupling with an intermediate system is described. This method is applied to a simple experimental realizable situation for entangling two spatially separated cavities. In this scheme entanglement, initially stored in two modes of the first cavity, is transferred by an atom interacting successively with the cavities, into entanglement between two non resonant modes of the different cavities.