255,457 research outputs found
Nested entangled states for distributed quantum channels
We find a coupling-strength configuration for a linear chain of N spins which
gives rise to simultaneous multiple Bell states. We suggest a way such an
interesting entanglement pattern can be used in order to distribute maximally
entangled channels to remote locations and generate multipartite entanglement
with a minimum-control approach. Our proposal thus provides a way to achieve
the core resources in distributed information processing. The schemes we
describe can be efficiently tested in chains of coupled cavities interacting
with three-level atoms.Comment: 4 pages, 2 figures, RevTeX
Extraction of Singlet States from Noninteracting High-Dimensional Spins
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.Comment: 4 pages, 2 figure
Knudsen Effect in a Nonequilibrium Gas
From the molecular dynamics simulation of a system of hard-core disks in
which an equilibrium cell is connected with a nonequilibrium cell, it is
confirmed that the pressure difference between two cells depends on the
direction of the heat flux. From the boundary layer analysis, the velocity
distribution function in the boundary layer is obtained. The agreement between
the theoretical result and the numerical result is fairly good.Comment: 4pages, 4figure
Deep ROSAT-HRI observation of the elliptical galaxy NGC 1399
We present the preliminary results of a deep (167 ks) ROSAT HRI observation
of the cD galaxy NGC1399 in the Fornax cluster. We find, in agreement with
previous observations, an extended (41 Kpc adopting a distance of 19 Mpc)
gaseous halo with a luminosity of L_X=(4.41\pm 0.04)x10^{41} erg/s. The 5
arcsec resolution of the data allows us to detect a very complex and asymmetric
structure of the halo with respect to the optical galaxy. Moreover the analysis
of the radial structure reveals the presence of a multi-component profile not
consistent with a simple King model over the whole 40 Kpc. We do not detect the
presence of a central source and pose an upper limit to the luminosity of a
possible active nucleus. Due to the length of the observation, comparable to
that of a deep survey, we detect a large number of sources within the HRI FOV,
in slight excess with respect to the estimates based on previous surveys. We
study the flux distribution of the sources, their temporal behaviour and their
spatial distribution with respect to the central galaxy.Comment: 15 pages, 10 figures (6 in color), 1 table; uses subfigure.sty,
supertabular.sty, lscape.sty, color.sty; To be published in the proceeding of
"X-ray Astronomy 2000" (Mondello (Palermo), September 2000
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