QUANTUM TELEPORTATION VIA 1D OPTICAL LATTICE CHAINS WITH NONLINEAR COUPLING

2008 ◽  
Vol 06 (06) ◽  
pp. 1213-1222
Author(s):  
JIN-LIANG GUO ◽  
JIE SONG ◽  
HE-SHAN SONG

We study quantum teleportation by using 1D optical lattice for two particles with nonlinear coupling in an external uniform magnetic field as resources via the standard teleportation protocol T0. The effects of linear coupling J, nonlinear coupling K and magnetic field B on the average fidelity are investigated in detail. It is found that increasing |K| is not only very helpful for enhancing the average fidelity, but also beneficial to improving the critical temperature Tf and magnetic field Bf, beyond which quantum teleportation is inferior to classical communication protocol.

2014 ◽  
Vol 92 (5) ◽  
pp. 406-410 ◽  
Author(s):  
Nour Zidan

Quantum teleportation via the entanglement channel composed of a two-qubit Heisenberg XYZ chain with Dzyaloshinskii–Moriya interaction in the presence of both inhomogeneous external magnetic field and intrinsic decoherence has been investigated. It is shown that the initial state of the channel plays an important role in the fully entangled fraction and the average fidelity of teleportation. It is found that when the initial system is in the entangled state |Ψ⟩ = m2|01⟩ + n2|10⟩ the corresponding average fidelity is always larger than 2/3.


Fluids ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 177 ◽  
Author(s):  
Tagawa

Linear stability analysis of liquid metal flow driven by a constant pressure gradient in an insulating rectangular duct under an external uniform magnetic field was carried out. In the present analysis, since the Joule heating and induced magnetic field were neglected, the governing equations consisted of the continuity of mass, momentum equation, Ohm’s law, and conservation of electric charge. A set of linearized disturbance equations for the complex amplitude was decomposed into real and imaginary parts and solved numerically with a finite difference method using the highly simplified marker and cell (HSMAC) algorithm on a two-dimensional staggered mesh system. The difficulty of the complex eigenvalue problem was circumvented with a Newton—Raphson method during which its corresponding eigenfunction was simultaneously obtained by using an iterative procedure. The relation among the Reynolds number, the wavenumber, the growth rate, and the angular frequency was successfully obtained for a given value of the Hartmann number as well as for a direction of external uniform magnetic field.


Author(s):  
Haim H. Bau ◽  
Jianzhong Zhu ◽  
Shizhi Qian ◽  
Yu Xiang

The magneto hydrodynamic fluidic network’s basic building blocks are conduits equipped with two electrodes positioned on opposing walls. The entire device is either subjected to an external uniform magnetic field or fabricated within a magnetic material. When a prescribed potential difference is applied across each electrode pair, it induces current in the liquid (assumed to be a weakly conductive). The current interacts with the magnetic field to produce a Lorentz force that is perpendicular to both the directions of the current and the magnetic field. Analogously with electric circuits, by judicious application of the potential differences at various branches, one can direct liquid flow in any desired way and rate without a need for mechanical pumps or valves. By equipping the network branches with additional, interior electrodes, the branches double as stirrers capable of generating chaotic advection. The paper describes the basic building blocks for such a network, the operation of these branches as stirrers, a general theory for the analysis and control of fluidic magneto-hydrodynamic networks, and an example of a network fabricated with low temperature, co-fired ceramic tapes.


Fluids ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 154
Author(s):  
Alessandra Borrelli ◽  
Giulia Giantesio ◽  
Maria Cristina Patria

In this paper, we describe our study of the mixed convection of a Boussinesquian Bingham fluid in a vertical channel in the absence and presence of an external uniform magnetic field normal to the walls. The velocity, the induced magnetic field, and the temperature are analytically obtained. A detailed analysis is conducted to determine the plug regions in relation to the values of the Bingham number, the buoyancy parameter, and the Hartmann number. In particular, the velocity decreases as the Bingham number increases. Detailed considerations are drawn for the occurrence of the reverse flow phenomenon. Moreover, a selected set of diagrams illustrating the influence of various parameters involved in the problem is presented and discussed.


2002 ◽  
Vol 16 (09) ◽  
pp. 1363-1379 ◽  
Author(s):  
L. CAMPOS VENUTI ◽  
E. ERCOLESSI ◽  
G. MORANDI ◽  
P. PIERI ◽  
M. RONCAGLIA

We investigate both numerically and analytically the behavior of a spin-1 antiferromagnetic isotropic Heisenberg chain in an external uniform magnetic field. Extensive DMRG studies of chains up to N = 80 sites extend previous analyses and obtain the zero-temperature correlation functions. We argue that, despite the presence of a magnetic field, the model is still well described by an O(3) nonlinear σ-model. A saddle-point analysis, that also includes Gaussian fluctuations, is developed for the latter both at zero and finite temperatures. Its predictions are compared with those of the numerical analysis and with the existing experimental literature.


In this paper, we investigated a new large-scale instability that arises in an obliquely rotating convective electrically conducting fluid in an external uniform magnetic field with a small-scale external force with zero helicity. This force excites small-scale velocity oscillations with a small Reynolds number. Using the method of multiscale asymptotic expansions, we obtain the nonlinear equations for vortex and magnetic disturbances in the third order of the Reynolds number. It is shown that the combined effects of the Coriolis force and the small external forces in a rotating conducting fluid possible large-scale instability. The linear stage of the magneto-vortex dynamo arising as a result of instabilities of -effect type is investigated. The mechanism of amplification of large-scale vortex disturbances due to the development of the hydrodynamic - effect taking into account the temperature stratification of the medium is studied. It was shown that a «weak» external magnetic field contributes to the generation of large-scale vortex and magnetic perturbations, while a «strong» external magnetic field suppresses the generation of magnetic-vortex perturbations. Numerical methods have been used to find stationary solutions of the equations of a nonlinear magneto-vortex dynamo in the form of localized chaotic structures in two cases when there is no external uniform magnetic field and when it is present.


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