3,900 research outputs found
Entanglement convertibility by sweeping through the quantum phases of the alternating bonds chain
We study the entanglement structure and the topological edge states of the
ground state of the spin-1/2 XXZ model with bond alternation. We employ
parity-density matrix renormalization group with periodic boundary conditions.
The finite-size scaling of R\'enyi entropies and are used to
construct the phase diagram of the system. The phase diagram displays three
possible phases: Haldane type (an example of symmetry protected topological
ordered phases), Classical Dimer and N\'eel phases, the latter bounded by two
continuous quantum phase transitions. The entanglement and non-locality in the
ground state are studied and quantified by the entanglement convertibility. We
found that, at small spatial scales, the ground state is not convertible within
the topological Haldane dimer phase. The phenomenology we observe can be
described in terms of correlations between edge states. We found that the
entanglement spectrum also exhibits a distinctive response in the topological
phase: the effective rank of the reduced density matrix displays a specifically
large "susceptibility" in the topological phase. These findings support the
idea that although the topological order in the ground state cannot be detected
by local inspection, the ground state response at local scale can tell the
topological phases apart from the non-topological phases.Comment: Final versio
A Multicriteria Analysis on the Strategies to Open Taiwan's Mobile Virtual Network Operators Services
[[abstract]]This study investigates the trends followed by MVNOs (Mobile Virtual Network Operators) in the last three years and analyzes the strategies that can contribute to the success of Taiwan's telecommunications industry and marketing. We apply the method and concept of PATTERN (Planning Assistance Through Technical Evaluation of Relevance Number) to establish relevant systems for searching out the key successful factors of strategies to attract MVNOs. We also use the fuzzy Multi-Criteria Decision Making (MCDM) method for analyzing the different preference of a decision group in the criteria weights and for ranking the alternatives in a fuzzy environment in order to provide a strategy scheme. These results provide a reference to assist telecommunications operators, 3G license owners, potential MVNOs, and equipment manufacturers when working out business plans.[[incitationindex]]SCI[[booktype]]紙
Uniform tiling with electrical resistors
The electric resistance between two arbitrary nodes on any infinite lattice
structure of resistors that is a periodic tiling of space is obtained. Our
general approach is based on the lattice Green's function of the Laplacian
matrix associated with the network. We present several non-trivial examples to
show how efficient our method is. Deriving explicit resistance formulas it is
shown that the Kagom\'e, the diced and the decorated lattice can be mapped to
the triangular and square lattice of resistors. Our work can be extended to the
random walk problem or to electron dynamics in condensed matter physics.Comment: 22 pages, 14 figure
Angular Dependences of Third Harmonic Generation from Microdroplets
We present experimental and theoretical results for the angular dependence of
third harmonic generation (THG) of water droplets in the micrometer range (size
parameter ). The THG signal in - and -polarization obtained
with ultrashort laser pulses is compared with a recently developed nonlinear
extension of classical Mie theory including multipoles of order .
Both theory and experiment yield over a wide range of size parameters
remarkably stable intensity maxima close to the forward and backward direction
at ``magic angles''. In contrast to linear Mie scattering, both are of
comparable intensity.Comment: 4 pages, RevTeX, 3 figures available on request from
[email protected], submitted to PR
Neurogenetic and genomic approaches reveal roles for Dpr/DIP cell adhesion molecules in Drosophila reproductive behavior
Drosophila reproductive behaviors are directed by fruitless neurons (fru P1 isoforms). A reanalysis of genomic studies shows that genes encoding dpr and DIP Immunoglobulin superfamily (IgSF) members are expressed in fru P1 neurons. Each fru P1and dpr/DIP (fru P1 ∩ dpr/DIP) overlapping expression pattern is similar in both sexes, with dimorphism in neuronal morphology and cell number. Behavioral studies of fru P1 ∩ dpr/DIP perturbation genotypes point to the mushroom body functioning together with the lateral protocerebral complex. Functionally, we find that perturbations of sex hierarchy genes and DIP-ε changes sex-specific morphology of fru P1 ∩ DIP-α neurons. A single-cell RNA-seq analysis shows that the DIPs have high expression in a restricted set of fru P1 neurons, whereas the dprs are expressed in larger set of neurons at intermediate levels, with a myriad of combinations
Effects of anharmonic strain on phase stability of epitaxial films and superlattices: applications to noble metals
Epitaxial strain energies of epitaxial films and bulk superlattices are
studied via first-principles total energy calculations using the local-density
approximation. Anharmonic effects due to large lattice mismatch, beyond the
reach of the harmonic elasticity theory, are found to be very important in
Cu/Au (lattice mismatch 12%), Cu/Ag (12%) and Ni/Au (15%). We find that
is the elastically soft direction for biaxial expansion of Cu and Ni, but it is
for large biaxial compression of Cu, Ag, and Au. The stability of
superlattices is discussed in terms of the coherency strain and interfacial
energies. We find that in phase-separating systems such as Cu-Ag the
superlattice formation energies decrease with superlattice period, and the
interfacial energy is positive. Superlattices are formed easiest on (001) and
hardest on (111) substrates. For ordering systems, such as Cu-Au and Ag-Au, the
formation energy of superlattices increases with period, and interfacial
energies are negative. These superlattices are formed easiest on (001) or (110)
and hardest on (111) substrates. For Ni-Au we find a hybrid behavior:
superlattices along and like in phase-separating systems, while for
they behave like in ordering systems. Finally, recent experimental
results on epitaxial stabilization of disordered Ni-Au and Cu-Ag alloys,
immiscible in the bulk form, are explained in terms of destabilization of the
phase separated state due to lattice mismatch between the substrate and
constituents.Comment: RevTeX galley format, 16 pages, includes 9 EPS figures, to appear in
Physical Review
Spanning trees on the Sierpinski gasket
We obtain the numbers of spanning trees on the Sierpinski gasket
with dimension equal to two, three and four. The general expression for the
number of spanning trees on with arbitrary is conjectured. The
numbers of spanning trees on the generalized Sierpinski gasket
with and are also obtained.Comment: 20 pages, 8 figures, 1 tabl
A particle-hole model approach for hypernuclei
A particle-hole model is developed to describe the excitation spectrum of
single lambda hypernuclei and the possible presence of collective effects is
explored by making a comparison with the mean-field calculations. Results for
the spectra of 12C, 16O, 40Ca, 90Zr and 208Pb single lambda hypernuclei are
shown. The comparison with the available experimental data is satisfactory. We
find that collective phenomena are much less important in hypernuclei than in
ordinary nuclei.Comment: 24 pages, 5 eps figures, accepted for publication in Nucl. Phys.
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