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151.
Pavičić M 《Physical review letters》2011,107(8):080403
For a reliable implementation of quantum teleportation, a near-deterministic (close to 100%) discrimination of all four Bell states of entangled qubits is required. One can carry it out with linear optical elements only if conditional dynamics are allowed. Here we present a setup in which we repeatedly disentangle and reentangle photons in three of four states, so as to separate photons in one of them, conditioned on keeping the other two at bay. The efficiency of a realistic implementation of our setup with current technology is over 90% for an ideal source of photons on demand. 相似文献
152.
Mordecai Waegell P. K. Aravind Norman D. Megill Mladen Pavičić 《Foundations of Physics》2011,41(5):883-904
The set of 60 real rays in four dimensions derived from the vertices of a 600-cell is shown to possess numerous subsets of
rays and bases that provide basis-critical parity proofs of the Bell-Kochen-Specker (BKS) theorem (a basis-critical proof
is one that fails if even a single basis is deleted from it). The proofs vary considerably in size, with the smallest having
26 rays and 13 bases and the largest 60 rays and 41 bases. There are at least 90 basic types of proofs, with each coming in
a number of geometrically distinct varieties. The replicas of all the proofs under the symmetries of the 600-cell yield a
total of almost a hundred million parity proofs of the BKS theorem. The proofs are all very transparent and take no more than
simple counting to verify. A few of the proofs are exhibited, both in tabular form as well as in the form of MMP hypergraphs
that assist in their visualization. A survey of the proofs is given, simple procedures for generating some of them are described
and their applications are discussed. It is shown that all four-dimensional parity proofs of the BKS theorem can be turned
into experimental disproofs of noncontextuality. 相似文献
153.
One can use a single optical cavity as the simplest possible resonator in order to ascertain the presence of an object with
an arbitrarily low portion of an incoming laser beam. In terms of individual photons, each photon nonrepeatedly tests the
object with an arbitrarily high probability of detecting its presence without interacting with it. 相似文献
154.
Alexander G. Andreev Stefka G. Tsintsarska Maria Dimitrova-Ivanovich Ivaylo Polyanski Mladen Georgiev Alexander D. Gochev 《Central European Journal of Physics》2004,2(2):329-356
The temperatureT dependencies ρ(T) of normal state electric resistivitiesρ
c
(axial) andρ
ab
(in plane) of single-layer high-T
c
superconductors show common trends: AsT is raised, the resistivity first drops steeply before it starts rising αT above an apparent semiconductor-to-metal crossoverT
cross
. To analyze ρ(T) we plottT/ρ againstT at various dopingsx for bothρ
c
andρ
ab
.T/ρ is inversely proportional to the traversal time across a potential barrier as an ionic particle drifts in an electric field.
We findT/ρ in good agreement with theT dependence of the quantum rate of migrating particles: AsT is raised, a zero-point rate at the lowestT is extended to a nearly flat plateau before a thermally activated branch sets in. We also find evidence for the admixture
of 1- & 2-phonon absorptions below the Arrhenius range. These features shape the semiconductor-like branch below T
cross
. AboveT
cross
a metallic-like branch sets in, its αT character deriving from the field coupling of the migrating particle. Our analysis suggests that metal physics may not suffice
if ionic features play a role in transport. We attribute our conclusions to the drift of strong-coupling polarons along Cu−O
bonds. These “bond polarons” originate from carrier scattering by double-well potentials associated with the bonds. A bond
polaron dissociates to a free hole as it passes onto a neighboring O-O link. 相似文献
155.
Mladen Božičević 《Mediterranean Journal of Mathematics》2007,4(4):407-418
Let G be a real Lie group acting on real analytic manifold with finitely many orbits. We prove that the characteristic cycle map
is a surjective homomorphism from the K-group of G-equivariant sheaves on X to the top homology group of the conormal variety of the G-action on X. We also show that the top homology group of the G-action on X is a free -module of rank equal to the number of G-orbits.
This work was completed with the support of the Ministry of Science, Education and Sport of Croatia, and Infodesign d.o.o.,
Varaždin. 相似文献
156.
Dzolić Z Cametti M Dalla Cort A Mandolini L Zinić M 《Chemical communications (Cambridge, England)》2007,(34):3535-3537
Anthraquinone derived oxalamide gelator 1 forms with aromatic solvents and alcohols very stable gels which selectively respond to the presence of fluoride anion by colour change and/or gel-to-sol transition. 相似文献
157.
Krajacić M Ivancic-Jelecki J Forcic D Vrdoljak A Skorić D 《Journal of chromatography. A》2007,1144(1):111-119
Replicative double-stranded RNA (dsRNA) is useful in preliminary identification of Cucumber mosaic virus and its satellite RNA (satRNA). This plant pathogen complex yields sufficient quantity of the replicative RNA form that can be isolated by chromatography on chemically unmodified graded cellulose powder (CF-11). In this work, much faster and more efficient procedure using DEAE monoliths was developed in which dsRNA was separated from other species in total nucleic acids extract originating from the infected plant tissue. The developed chromatographic method revealed the pathogens' presence in only 15 min, avoiding nucleic acid precipitation and electrophoretic analysis. 相似文献
158.
The response to photodynamic therapy (PDT) mediated by photosensitizer Photofrin was examined with Lewis lung carcinomas growing in either complement-proficient C57BL/6 (B6) or complement-deficient complement C3 knockout (C3KO) mice. The results reveal that Photofrin-PDT was more effective in attaining cures of tumors in C3KO than in B6 hosts. Colony-forming ability of cells from tumors excised immediately after Photofrin-PDT confirmed that the direct cell killing effect was more pronounced in C3KO than in B6 hosts. In contrast, PDT mediated by photosensitizer benzoporphyrin derivative (BPD) produced higher cure rates of tumors in B6 hosts than those in C3KO hosts. Determination of tumor C3 levels by ELISA showed that Photofrin-PDT induced markedly more pronounced complement activation than BPD-PDT. Measurements of tumor oxygen tension immediately after PDT by Eppendorf pO2 histograph showed that Photofrin-PDT induced a marked decline in the oxygenation of tumors growing in B6 mice that was much less pronounced in C3KO hosts. With BPD-PDT the oxygen tensions in tumors in B6 and C3KO hosts decreased to a similar extent. This study indicates that complement activation in PDT-treated tumors that varies with different photosensitizers is an important determinant of tumor oxygen limitation effects directly associated with photodynamic action. 相似文献
159.
Aminocoumarin derivatives 3‐10 were condensed with diethyl ethoxymethylenemalonate to give intermediates 11‐18. Thermal cyclizations of intermediates give benzopyranopyridinecarboxylates 19‐26. These esters were hydrolyzed to the corresponding benzopyranopyridine carboxylic acids 27‐34. 相似文献
160.
Mladen Božiĉević 《manuscripta mathematica》1994,85(1):217-226
LetG be a complex semisimple Lie group,B its Borel subgroup andX a flag variety ofG. We define a functor on the category ofB-equivariantD
X-modules that corresponds, under the global section functor, to the Enright functor on the highest weight category. We use
this to lift Enright functor to the mixed version of the highest weight category. As an application we obtain that the socle
and the cosocle filtration of a primitive quotient of the enveloping algebra coincide. 相似文献