Exact solution at integrable coupling of a model for the Josephson effect between small metallic grains

A model is introduced for two reduced BCS systems which are coupled through the transfer of Cooper pairs between the systems. The model may thus be used in the analysis of the Josephson effect arising from pair tunneling between two strongly coupled small metallic grains. At a particular coupling strength the model is integrable and explicit results are derived for the energy spectrum, conserved operators, integrals of motion, and wave function scalar products. It is also shown that form factors can be obtained for the calculation of correlation functions. Further, a connection with perturbed conformal field theory is made.Comment: 12 pages, latex, no figure

Determinants of Economic Growth in China

China is one of the strongest economies in the world which is only second to the United States. Over the past four decades, China was experiencing a fast economic growth and its rise from a developing country to a significant economic power is spectacular. The researchers try to identify main determinants of economic growth using annual data from 1982 to 2018.Multiple regression analysis using OLS method was employed to investigate the influence of each explanatory variable on the GDP per capita growth rate. The results indicate that the education level and foreign direct investment (FDI) inflows have positive and significant impact on economic growth while population growth has imposed a negative and significant impact on growth. As results suggest, education level has played a major role in achieving higher growth rates in China. At present, 4 per cent of China's total GDP is invested in education. If the government can promote education in China, it would promote economic growth further. This study proves that FDI inflows also have a significant positive influence on economic growth. China has imposed a number of restrictions on FDI inflows. However, according to the results of this study, if the policymakers can open up the economy to facilitate FDI inflows, it would promote economic growth in China significantly. Due to the one-child policy, China is still maintaining a very lower population growth. Due to this, China has faced a severe demographic problem of aging population. That problem has led to slow down the economic growth in China. Keywords: Economic growth, education level, foreign direct investments, population growth, Chin

Dynamics of glass phases in the two-dimensional gauge glass model

Large-scale simulations have been performed on the current-driven two-dimensional XY gauge glass model with resistively-shunted-junction dynamics. It is observed that the linear resistivity at low temperatures tends to zero, providing strong evidence of glass transition at finite temperature. Dynamic scaling analysis demonstrates that perfect collapses of current-voltage data can be achieved with the glass transition temperature $T_{g}=0.22$, the correlation length critical exponent $\nu =1.8$, and the dynamic critical exponent $z=2.0$. A genuine continuous depinning transition is found at zero temperature. For creeping at low temperatures, critical exponents are evaluated and a non-Arrhenius creep motion is observed in the glass phase.Comment: 10 pages, 6 figure

Geometric entanglement from matrix product state representations

An efficient scheme to compute the geometric entanglement per lattice site for quantum many-body systems on a periodic finite-size chain is proposed in the context of a tensor network algorithm based on the matrix product state representations. It is systematically tested for three prototypical critical quantum spin chains, which belong to the same Ising universality class. The simulation results lend strong support to the previous claim [Q.-Q. Shi, R. Or\'{u}s, J. O. Fj{\ae}restad, and H.-Q. Zhou, New J. Phys \textbf{12}, 025008 (2010); J.-M. St\'{e}phan, G. Misguich, and F. Alet, Phys. Rev. B \textbf{82}, 180406R (2010)] that the leading finite-size correction to the geometric entanglement per lattice site is universal, with its remarkable connection to the celebrated Affleck-Ludwig boundary entropy corresponding to a conformally invariant boundary condition.Comment: 4+ pages, 3 figure

Characterization of the Superhyperfine Interaction in ^(171)Yb:YVO_4

We computationally characterize the superhyperfine energy structure of ^(171)Yb:YVO_4 and compare predicted holeburning spectra and coherence times with experimental data. Our simulation can help optimize coherence times for ensemble-based quantum memories and single-ion qubits

Antibacterial Mechanism of the Ehyl Acetate Extracts From Naked Oat Again Bacillus Subtilis

The antibacterial mechanism of the ethyl acetate extracts from naked oat against Bacillus subtilis were studied in this paper based on assays such as cell wall alkaline phosphatase (AKP), permeability and integrity of cell membrane as well as electron microscopy observations. The results showed that the ethyl acetate extracts had significant effects on AKP, permeability and integrity of cell membrane. We concluded that the mechanism of action of the ethyl acetate extracts against B. subtilis might be described as:Acting on cell wall and membrane, resulting in disruption, cell lysis, and the leakage of intracellular constituents according to the results of AKP, the leakage of electrolytes, the losses of contents (proteins, reducing sugars and 260 nm absorbing materials) assays and electron microscopy observations. Overall, the results clearly indicated that the ethyl acetate extracts from naked oat was potential to control the contamination of foods caused by bacterial disease

Ground-State Fidelity and Kosterlitz-Thouless Phase Transition for Spin 1/2 Heisenberg Chain with Next-to-the-Nearest-Neighbor Interaction

The Kosterlitz-Thouless transition for the spin 1/2 Heisenberg chain with the next-to-the-nearest-neighbor interaction is investigated in the context of an infinite matrix product state algorithm, which is a generalization of the infinite time-evolving block decimation algorithm [G. Vidal, Phys. Rev. Lett. \textbf{98}, 070201 (2007)] to accommodate both the next-to-the-nearest-neighbor interaction and spontaneous dimerization. It is found that, in the critical regime, the algorithm automatically leads to infinite degenerate ground-state wave functions, due to the finiteness of the truncation dimension. This results in \textit{pseudo} symmetry spontaneous breakdown, as reflected in a bifurcation in the ground-state fidelity per lattice site. In addition, this allows to introduce a pseudo-order parameter to characterize the Kosterlitz-Thouless transition.Comment: 4 pages, 4 figure

Fluorophore-Doped Core-Multishell Spherical Plasmonic Nanocavities: Resonant Energy Transfer towards a Loss Compensation

Cataloged from PDF version of article.Plasmonics exhibits the potential to break the diffraction limit and bridge the gap between electronics and photonics by routing and manipulating light at the nanoscale. However, the inherent and strong energy dissipation present in metals, especially in the near-infrared and visible wavelength ranges, significantly hampersthe applications in nanophotonics. Therefore, it is amajor challengetomitigatethe losses. One way to compensate the losses is to incorporate gain media into plasmonics. Here, we experimentally show that the incorporation of gain material into a local surface plasmonic system (Au/silica/silica dye core multishell nanoparticles) leads to a resonant energy transfer from the gain media to the plasmon. The optimized conditions for the largest loss compensation are reported. Both the coupling distance and the spectral overlap arethe key factorsto determinetheresulting energy transfer. Theinterplay of these factors leadsto a non-monotonous photoluminescence dependence as a function of the silica spacer shell thickness. Nonradiativetransferrate is increased by morethan 3 orders of magnitude attheresonant condition, which is key evidence of the strongest coupling occurring between the plasmon and the gain material