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The global geometric entanglement (GE) is studied in the context of newly developed tensor network algorithms for finite systems. For onedimensional quantum spin systems it is found that, at criticality, the leading finite-size correction to the global GE per site behaves as b/n, where n is the size of the system and b a given coefficient. Our conclusion is based on the computation of the GE per spin for the quantum Ising model in a transverse magnetic field and for the spin-1/2 XXZ model. We also discuss the possibility of coefficient b being universal. [ABSTRACT FROM AUTHOR]

Five duality transformations are unveiled for the quantum XYZ model with arbitrary spin in one spatial dimension. The presence of these duality transformations, together with an extra Hamiltonian symmetry, drastically reduce the entire ground-state phase diagram to two finite regimes—the principal regimes, with all the other ten regimes dual to them. Combining with the determination of critical points from the conventional order parameter approach and/or the fidelity approach to quantum phase transitions, we are able to map out the ground-state phase diagram for the quantum XYZ model with arbitrary spin . This is explicitly demonstrated for and 2. As it turns out, all the critical points, with central charge , are self-dual for half-integer as well as integer spin . However, in the latter case, the presence of the Haldane phase results in extra lines of critical points with central charge , which are not self-dual. [ABSTRACT FROM AUTHOR]

In this paper, a computational model is constructed to investigate the phenomenon of the initial plasma formation and current transfer in the single-wire electrical explosion in a vacuum. The process of the single-wire electrical explosion is divided into four stages. Stage I: the wire is in solid state. Stage II: the melting stage. Stage III: the wire melts completely and the initial plasma forms. Stage IV: the core and corona expand separately. The thermodynamic calculation is applied before the wire melts completely in stages I and II. In stage III, a one-dimensional magnetohydrodynamics model comes into play until the instant when the voltage collapse occurs. The temperature, density, and velocity, which are derived from the magnetohydrodynamics calculation, are averaged over the distribution area. The averaged parameters are taken as the initial conditions for stage IV in which a simplified magnetohydrodynamics model is applied. A wide-range semi-empirical equation of state, which is established based on the Thomas–Fermi–Kirzhnits model, is constructed to describe the phase transition from solid state to plasma state. The initial plasma formation and the phenomenon of current transfer in the electrical explosion of aluminum wire are investigated using the computational model. Experiments of electrical explosion of aluminum wires are carried out to verify this model. Simulation results are also compared with experimental results of the electrical explosion of copper wire. [ABSTRACT FROM AUTHOR]

A semi-empirical equation of state model for aluminum in a warm dense matter regime is constructed. The equation of state, which is subdivided into a cold term, thermal contributions of ions and electrons, covers a broad range of phase diagram from solid state to plasma state. The cold term and thermal contribution of ions are from the Bushman–Lomonosov model, in which several undetermined parameters are fitted based on equation of state theories and specific experimental data. The Thomas–Fermi–Kirzhnits model is employed to estimate the thermal contribution of electrons. Some practical modifications are introduced to the Thomas–Fermi–Kirzhnits model to improve the prediction of the equation of state model. Theoretical calculation of thermodynamic parameters, including phase diagram, curves of isothermal compression at ambient temperature, melting, and Hugoniot, are analyzed and compared with relevant experimental data and other theoretical evaluations. [ABSTRACT FROM AUTHOR]

Two new two-photon absorption (TPA) molecules, named SK-G1 and NT-G1, are synthesized and the photo-physical characteristics are investigated by using linear absorption spectra, one-photon fluorescence spectra and two-photon excited fluorescence spectra. Both the compounds exhibit TPA properties, and the TPA values determined by z-scan measurement are 10GMand 39GMfor SK-G1 and NT-G1, respectively, at wavelength 800nm. Time-resolved spectroscopic techniques are employed to further explore the excited state dynamics of NT-G1with larger TPA cross section. The research results show that there is an ultrafast intraband energy transfer process (about 3ps) before the formation of charge transfer state with a relatively long lifetime. [ABSTRACT FROM AUTHOR]

Two soluble polymer grafted multi-walled carbon nanotubes (MWNTs), including poly(N-vinylcarbazole)-MWNTs and poly(methyl methacrylate)-MWNTs, are synthesized. Their nonlinear optical properties and optical limiting (OL) performances are investigated by z-scan method with 527nm nanosecond laser pulses. These grafted MWNTs dissolved in chloroform show much better optical limiting performance than those of MWNTs and C60 in toluene solution. Nonlinear absorption and nonlinear scattering mechanism are taken into consideration for explaining the observed results. The comparison of the experimental results shows that nonlinear absorption is the dominant mechanism for OL performance of these new samples. [ABSTRACT FROM AUTHOR]

Ultrafast third-order optical nonlinearities of the as-deposited and annealed Au:Bi2O3 nanocomposite films deposited by magnetron cosputtering are investigated by using femtosecond time-resolved optical Kerr effect (OKE) and pump-probe techniques. The third-order optical nonlinear susceptibility is estimated to be 2.6x10[?]10 esu and 1.8x10[?]9 esu at wavelength of 800 nm, for the as-deposited and the annealed film, respectively. The OKE signal of the as-deposited film is nearly temporally symmetrical with a peak centred at zero delay time, which indicates the dominant contribution from intraband transition of conduction electrons. For the annealed film, the existence of a decay process in OKE signal implies the important contribution of hot electrons. These characteristics are in agreement with the hot electron dynamics observed in pump-probe measurement. [ABSTRACT FROM AUTHOR]

We reported a study of tunnel magnetoresistance (TMR) effect in single manganite nanowire via the combination of magnetotransport and magnetic force microscopy imaging. TMR value up to 290% has been observed in single (La1 − yPry)1 − xCaxMnO3 nanowires with varying width. We find that the TMR effect can be explained in the scenario of opening and blockade of conducting channels from inherent magnetic domain evolutions. Our findings provide a new route to fabricate TMR junctions and point towards future improvements in complex oxide-based TMR spintronics. [ABSTRACT FROM AUTHOR]