344 research outputs found
Quantum state redistribution based on a generalized decoupling
We develop a simple protocol for a one-shot version of quantum state
redistribution, which is the most general two-terminal source coding problem.
The protocol is simplified from a combination of protocols for the fully
quantum reverse Shannon and fully quantum Slepian-Wolf problems, with its
time-reversal symmetry being apparent. When the protocol is applied to the case
where the redistributed states have a tensor power structure, more natural
resource rates are obtained
A Spectroscopic Study on PtCl4(2−) Binding to Rabbit Skeletal Muscle G-Actin
It was found that the binding of PtCl42−
to G-actin and the consequent conformational
changes are different with those for hard acids. It is a two-step process depending on molar
ratio PtCl42−/actin (R). In the first step, R less than 25, the PtCl42− ions are bound to
sulfur-containing groups preferentially. These high-affinity sites determined by Scatchard
approach are characterized by n1 = 30
with average binding constant K1=1.0×107M-1. The
conformational changes are significant as characterized by N-(1-pyrenyl) maleimide(NPM)
labeled fluorescence, intrinsic fluorescence and CD spectra. EPR spectroscopy of
maleimide spin labeled(MSL) actin demonstrated that even PtCl42−binding is limited to a
very small fraction of high-affinity sites(R<1), it can bring about a pronounced change of
conformation. In the range of R=25-40, high-affinity sites accessible are saturated. In the
second step(R>40)
, deep-buried binding sites turn out to be accessible as a result of the
accumulated conformational changes. These new binding sites are estimated to be n2=26
with average binding constant K2=2.1×106M-1. Although in this step the quenching of
intrinsic fluorescence goes on and the NPM-labled thiols moves to more hydrophilic
environment, no change in α-helix content was found. These results suggested that with
increasing in PtCl4(2−) binding, the G-actin turns to an open and loose structure in a
discontinuous mode
Exploration of nonlocalities in ensembles consisting of bipartite quantum states
It is revealed that ensembles consisting of multipartite quantum states can
exhibit different kinds of nonlocalities. An operational measure is introduced
to quantify nonlocalities in ensembles consisting of bipartite quantum states.
Various upper and lower bounds for the measure are estimated and the exact
values for ensembles consisting of mutually orthogonal maximally entangled
bipartite states are evaluated.Comment: The title and some contents changed, 4 pages, no figure
Exploring multipartite quantum correlations with the square of quantum discord
We explore the quantum correlation distribution in multipartite quantum
states based on the square of quantum discord (SQD). For tripartite quantum
systems, we derive the necessary and sufficient condition for the SQD to
satisfy the monogamy relation. Particularly, we prove that the SQD is
monogamous for three-qubit pure states, based on which a genuine tripartite
quantum correlation measure is introduced. In addition, we also address the
quantum correlation distributions in four-qubit pure states. As an example, we
investigate multipartite quantum correlations in the dynamical evolution of
multipartite cavity-reservoir systems.Comment: 8 pages, 5 figure
Entanglement in a class of multiqubit mixed states without multipartite tangles
Based on quantum complementary relations (QCRs) and a purification scenario,
we analyze a class of N-qubit mixed states that are entangled but do not have
two-, and genuine three-, four-, ..., N-qubit entanglements. It is shown that
entanglement (one-tangle or negativity) in these mixed states is closely
related to the QCR entanglement of their purified states. In particular, it is
elaborated that when the mixed state does not have multipartite tangles (two-
and higher tangles), its entanglement is actually a kind of genuine
multipartite QCR entanglement between the system and its environment.Comment: 5 pages, 3 figures, version
Observation of the Knot Topology of Non-Hermitian Systems in a Single Spin
The non-Hermiticity of the system gives rise to distinct knot topology that
has no Hermitian counterpart. Here, we report a comprehensive study of the knot
topology in gapped non-Hermitian systems based on the universal dilation method
with a long coherence time nitrogen-vacancy center in a C isotope
purified diamond. Both the braiding patterns of energy bands and the eigenstate
topology are revealed. Furthermore, the global biorthogonal Berry phase related
to the eigenstate topology has been successfully observed, which identifies the
topological invariance for the non-Hermitian system. Our method paves the way
for further exploration of the interplay among band braiding, eigenstate
topology and symmetries in non-Hermitian quantum systems
Effects of salt stress on interspecific competition between an invasive alien plant Oenothera biennis and three native species
Biological invasions and soil salinization have become increasingly severe environmental problems under global change due to sea-level rise and poor soil management. Invasive species can often outcompete native species, but few studies focus on whether invasive alien species are always superior competitors under increasing stressors. We grew an invasive grass species, Oenothera biennis L., and three native grass species (Artemisia argyi Lévl. et Vant., Chenopodium album L., and Inula japonica Thunb.) as a monoculture (two seedlings of each species) or mixture (one seedling of O. biennis and one native species seedling) under three levels of salt treatments (0, 1, and 2 g/kg NaCl) in a greenhouse. We found that invasive O. biennis exhibited greater performance over native C. album and I. japonica, but lower performance compared to A. argyi, regardless of the soil salinity. However, salinity did not significantly affect the relative dominance of O. biennis. Interspecific competition enhanced the growth of O. biennis and inhibited the growth of I. japonica. Although O. biennis seedlings always had growth dominance over C. album seedlings, C. album was not affected by O. biennis at any salt level. At high salt levels, O. biennis inhibited the growth of A. argyi, while A. argyi did not affect the growth of O. biennis. Salt alleviated the competitive effect of O. biennis on I. japonica but did not mitigate the competition between O. biennis and the other two native species. Therefore, our study provides evidence for a better understanding of the invasive mechanisms of alien species under various salinity conditions
A Facile Synthesis of ZnCo\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e Nanocluster Particles and the Performance as Anode Materials for Lithium Ion Batteries
ZnCo2O4 nanocluster particles (NCPs) were prepared through a designed hydrothermal method, with the assistance of a surfactant, sodium dodecyl benzene sulfonate. The crystalline structure and surface morphology of ZnCo2O4 were investigated by XRD, XPS, SEM, TEM, and BET analyses. The results of SEM and TEM suggest a clear nanocluster particle structure of cubic ZnCo2O4 (~100 nm in diameter), which consists of aggregated primary nanoparticles (~10 nm in diameter), is achieved. The electrochemical behavior of synthesized ZnCo2O4 NCPs was investigated by galvanostatic discharge/charge measurements and cyclic voltammetry. The ZnCo2O4 NCPs exhibit a high reversible capacity of 700 mAh g−1 over 100 cycles under a current density of 100 mA g−1 with an excellent coulombic efficiency of 98.9% and a considerable cycling stability. This work demonstrates a facile technique designed to synthesize ZnCo2O4 NCPs which show great potential as anode materials for lithium ion batteries
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