667 research outputs found
Scheme for preparation of mulipartite entanglement of atomic ensembles
We describe an experimental scheme of preparing multipartite W class of
maximally entangled states between many atomic ensembles. The scheme is based
on laser manipulation of atomic ensembles and single-photon detection, and well
fits the status of the current experimental technology. In addition, we show
one of the applications of the kind of W class states, teleporting an entangled
state of atomic ensembles with unknown coefficients to more than one distant
parties, either one of which equally likely receives the transmitted state.Comment: 4 pages, 3 figure
Single Molecule Michaelis-Menten Equation beyond Quasi-Static Disorder
The classic Michaelis-Menten equation describes the catalytic activities for
ensembles of enzyme molecules very well. But recent single-molecule experiment
showed that the waiting time distribution and other properties of single enzyme
molecule are not consistent with the prediction based on the viewpoint of
ensemble. It has been contributed to the slow inner conformational changes of
single enzyme in the catalytic processes. In this work we study the general
dynamics of single enzyme in the presence of dynamic disorder. We find that at
two limiting cases, the slow reaction and nondiffusion limits, Michaelis-Menten
equation exactly holds although the waiting time distribution has a
multiexponential decay behaviors in the nondiffusion limit.Particularly, the
classic Michaelis-Menten equation still is an excellent approximation other
than the two limits.Comment: 10 pages, 1 figur
Turbulence in outer protoplanetary disks: MRI or VSI?
The outer protoplanetary disks (PPDs) can be subject to the magnetorotational
instability (MRI) and the vertical shear instability (VSI). While both
processes can drive turbulence in the disk, existing numerical simulations have
studied them separately. In this paper, we conduct global 3D non-ideal
magnetohydrodynamic (MHD) simulations for outer PPDs with ambipolar diffusion
and instantaneous cooling, and hence conductive to both instabilities. Given
the range of ambipolar Els\"{a}sser numbers () explored, it is found that
the VSI turbulence dominates over the MRI when ambipolar diffusion is strong
(); the VSI and MRI can co-exist for ; and the VSI is overwhelmed
by the MRI when ambipolar diffusion is weak (). Angular momentum
transport process is primarily driven by MHD winds, while viscous accretion due
to MRI and/or VSI turbulence makes a moderate contribution in most cases.
Spontaneous magnetic flux concentration and formation of annular substructures
remain robust in strong ambipolar diffusion dominated disks () with
the presence of the VSI. Ambipolar diffusion is the major contributor to the
magnetic flux concentration phenomenon rather than advection.Comment: 9 pages, 10 figures, accepted for publication in MNRA
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