Tunable Goos-H\"{a}nchen shift and polarization beam splitter in electro-optic crystals

We have investigated the tunable lateral shift and polarization beam splitting of the transmitted light beam through electro-optic crystals, based on the Pockels effect. The positive and negative lateral shifts could be easily controlled by adjusting the permittivity tensor, which is modulated by the external applied electric field. An alternative way to realize the polarization beam splitter was also proposed by the polarization-dependent lateral shifts. Numerical simulations for Gaussian-shaped incident beam have demonstrated the above theoretical results obtained by stationary phase method. All these phenomena have potential applications in optical devices.Comment: 5 pages, 7 figure

Effects of ion motion on linear Landau damping

The effects of ion motion on Landau damping has been studied by the use of one-dimensional Vlasov-Poisson simulation. It is shown that the ion motion may significantly change the development of the linear Landau damping. When the ion mass is multiple of proton mass, its motion will halt the linear Landau damping at some time due to the excitation of ion acoustic waves. The latter will dominate the system evolution at the later stage and hold a considerable fraction of the total energy in the system. With very small ion mass, such as in electron-positron plasma, the ion motion can suppress the linear Landau damping very quickly. When the initial field amplitude is relatively high such as with the density perturbation amplitude δn/n0 > 0.1, the effect of ion motion on Landau damping is found to be weak or even ignorable

Neutralizing Monoclonal Antibodies Reduce Human Cytomegalovirus Infection and Spread in Developing Placentas.

Congenital human cytomegalovirus (HCMV) infection is a leading cause of birth defects worldwide, yet the most effective strategies for preventing virus transmission during pregnancy are unknown. We measured the efficacy of human monoclonal antibodies (mAbs) to HCMV attachment/entry factors glycoprotein B (gB) and the pentameric complex, gH/gL-pUL128-131, in preventing infection and spread of a clinical strain in primary placental cells and explants of developing anchoring villi. A total of 109 explants from five first-trimester placentas were cultured, and infection was analyzed in over 400 cell columns containing ~120,000 cytotrophoblasts (CTBs). mAbs to gB and gH/gL, 3-25 and 3-16, respectively, neutralized infection in stromal fibroblasts and trophoblast progenitor cells. mAbs to pUL128-131 of the pentameric complex, 1-103 and 2-18, neutralized infection of amniotic epithelial cells better than mAbs 3-25 and 3-16 and hyperimmune globulin. Select mAbs neutralized infection of cell column CTBs, with mAb 2-18 most effective, followed by mAb 3-25. Treatment of anchoring villi with mAbs postinfection reduced spread in CTBs and impaired formation of virion assembly compartments, with mAb 2-18 achieving better suppression at lower concentrations. These results predict that antibodies generated by HCMV vaccines or used for passive immunization have the potential to reduce transplacental transmission and congenital disease

Composite metamaterials with dual-band magnetic resonances in the terahertz frequency regime

Composite metamaterials(CMMs) combining a subwavelength metallic hole array (i.e. one-layer fishnet structure) and an array of split-ring resonators(SRRs) on the same board are fabricated with gold films on silicon wafer. Transmission measurements of the CMMs in the terahertz range have been performed. Dual-band magnetic resonances, namely, a LC resonance at 4.40 THz and an additional magnetic resonance at 8.64 THz originating from the antiparallel current in wire pairs in the CMMs are observed when the electrical field polarization of the incident light is parallel to the gap of the component SRR. The numerical simulations agree well with the experimental results and further clarify the nature of the dual-band magnetic resonances.Comment: 4 figures, 14 page

Efficient green-emitting Tb3+-doped di-ureasil coating phosphors for near-UV excited light-emitting diodes

Light-emitting diodes (LEDs) are replacing conventional lighting sources, like incandescent and fluorescent lamps, due to their higher efficiency, lower energy consumption and environmental friendliness characteristics. Additional applications envisaging “engineered light” able to control the human circadian rhythm are now in place with emphases on green-emitting LEDs. In this work, transparent and flexible coatings based on organic–inorganic di-ureasil hybrids doped in-situ with a terbium (Tb3+) complex involving salicylic acid as ligands were synthesized. The materials are transparent, essentially amorphous and thermal stable up to 180 °C. Under near-UV excitation, bright green emission with high quantum yield (0.565 ± 0.057) and enhanced photostability are observed. Green-emitting prototypes were fabricated using a commercial near-UV-emitting LED (NUV-LED) combined with the Tb3+-doped di-ureasil coating showing narrow-band green emission with yellowish-green color coordinates (Commission Internationale de l'Éclairage, CIE 1931) of (0.329, 0.606) and high luminous efficacy (21.5 lm/W). This efficacy is the largest one reported for analogous prototypes formed by an NUV-LED coated with a green-emitting phosphor prepared under mild synthetic conditions (<100 °C), demonstrating that in-situ formation of carboxylate lanthanide-based complexes is an energy saving process with potential for solid-state lighting and backlight for flexible displays.publishe

Movable Fiber-Integrated Hybrid Plasmonic Waveguide on Metal Film

A waveguide structure consisting of a tapered nanofiber on a metal film is proposed and analyzed to support highly localized hybrid plasmonic modes. The hybrid plasmonic mode can be efficiently excited through the in-line tapered fiber based on adiabatic conversion and collected by the same fiber, which is very convenient in the experiment. Due to the ultrasmall mode area of plasmonic mode, the local electromagnetic field is greatly enhanced in this movable waveguide, which is potential for enhanced coherence light emitter interactions, such as waveguide quantum electrodynamics, single emitter spectrum and nonlinear optics