Quantum correlation and classical correlation dynamics in the spin-boson model

We study the quantum correlation and classical correlation dynamics in a spin-boson model. For two different forms of spectral density, we obtain analytical results and show that the evolutions of both correlations depend closely on the form of the initial state. At the end of evolution, all correlations initially stored in the spin system transfer to reservoirs. It is found that for a large family of initial states, quantum correlation remains equal to the classical correlation during the course of evolution. In addition, there is no increase in the correlations during the course of evolution.Comment: 10 pages, 5 figure

A Novel Broadband Printed Dipole Antenna and Its Application for TD-LTE Communications

Novel double-sided printed dipole antennas are proposed and investigated in this paper. Two pairs of identical T-shape metallic loadings are connected to the traditional double-sided printed dipole, enhancing the operating bandwidth. Simulations show that the proposed printed dipole without the reflecting ground plane gives a bandwidth of up to 90.7% for S11<-10 dB or 84.9% for S11<-15 dB, which is significantly greater than those of the traditional printed dipole. The proposed dipole is then applied to design a dual-polarized printed dipole antenna, mounted on a ground plane. Measurements for the prototype show a bandwidth of 68.8% for S11<-10 dB, covering the entire TD-LTE band. The gain is about 6–8 dBi and the isolation is over 24 dB over the bandwidth

A Novel Broadband Printed Dipole Antenna and Its Application for TD-LTE Communications

Novel double-sided printed dipole antennas are proposed and investigated in this paper. Two pairs of identical T-shape metallic loadings are connected to the traditional double-sided printed dipole, enhancing the operating bandwidth. Simulations show that the proposed printed dipole without the reflecting ground plane gives a bandwidth of up to 90.7% for 11 &lt; −10 dB or 84.9% for 11 &lt; −15 dB, which is significantly greater than those of the traditional printed dipole. The proposed dipole is then applied to design a dual-polarized printed dipole antenna, mounted on a ground plane. Measurements for the prototype show a bandwidth of 68.8% for 11 &lt; −10 dB, covering the entire TD-LTE band. The gain is about 6-8 dBi and the isolation is over 24 dB over the bandwidth

Giant photoinduced lattice distortion in oxygen-vacancy ordered SrCoO2.5 thin films

Despite of the tremendous efforts spent on the oxygen vacancy migration in determining the property optimization of oxygen-vacancy enrichment transition metal oxides, few has focused on their dynamic behaviors non-equilibrium states. In this work, we performed multi-timescale ultrafast X-ray diffraction measurements by using picosecond synchrotron X-ray pulses and femtosecond table-top X-ray pulses to monitor the structural dynamics in the oxygen-vacancy ordered SrCoO2.5 thin films. A giant photoinduced strain ({\Delta}c/c > 1%) was observed, whose distinct correlation with the pump photon energy indicates a non-thermal origin of the photoinduced strain. The sub-picosecond resolution X-ray diffraction reveals the formation and propagation of the coherent acoustic phonons inside the film. We also simulate the effect of photoexcited electron-hole pairs and the resulting lattice changes using the Density Function Theory method to obtain further insight on the microscopic mechanism of the measured photostriction effect. Comparable photostrictive responses and the strong dependence on excitation wavelength are predicted, revealing a bonding to anti-bonding charge transfer or high spin to intermediate spin crossover induced lattice expansion in the oxygen-vacancy films.Comment: 12 pages, 4 figures, support materia

Crustal structure of the central Tibetan plateau and geological interpretation

Based on teleseismic data obtained from 225 stations from two networks in the central Tibetan plateau, we have generated detailed crustal structure images using P-wave receiver function techniques with more accurate piercing-depth-correction and time-depth-correction than what have previously been available. Our images indicate an undulatory Moho beneath the Tibetan plateau with a steep jump beneath the northern Himalaya, and obviously different structures in proximity to the Bangong-Nujiang suture. In several sections of the Tibetan plateau, the lower crust is characterized by pervasive high-velocity regions, which are consistent with the preservation of eclogite bodies beneath the plateau, whose presence affects the dynamics of the Tibetan plateau.China Earthquake Administration (Grant 201308013)National Natural Science Foundation (China) (Grants 40974034, 41174086, 41074052 and 41021003