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In the present manuscript, theoretical investigation of interface modes at the interface of two isotropic dielectric photonic crystals is performed. For both transverse electric ( σ - polarized waves) and transverse magnetic ( π - polarized waves) cases dispersive properties such as dispersion curve, photonic band gap (PBG) shrinking - optical holes and Brewster points are discussed. For the case of σ - polarized waves, interface modes are exhibited which are of prime importance in the present analysis. It is shown that for σ - polarized waves only DD (decaying-decaying) and DE (decaying-extending) type interface modes exist. On the other hand, for the case of π - polarized waves only EE (extending- extending) type interface modes exist which is completely transmitted through the photonic structure. Therefore, depending on the properties of the chosen materials, such photonic structure can seek different applications in the design of sensors, optical filters, optical switches, etc. and it is also suitable to explore the electromagnetic (EM) behaviour at the interface of various media. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetically polarizable Pickering oil-in-water nanoemulsion is prepared. • Inter-droplet force profiles are probed using magnetic chaining technique. • Colloidal stability is assessed at varying pH. • At higher salt concentration decay length decreases for mono, di and trivalent salts. • Screened coulombic & electric dipolar interactions contribute to total repulsion. The presence of nanoparticles at oil-water interface influences the interaction forces between Pickering emulsions. When charged nanoparticles are at the oil-water interface of an electrostatically stabilized emulsion, in addition to the screened Coulombic interaction, electric dipolar force also influences the total inter-droplet force profiles. An in-depth understanding of the effects of such electric dipolar forces is essential for designing colloidally stable Pickering nanoemulsions for various applications. Inter-droplet forces between γ-Al 2 O 3 nanoparticle stabilized oil-in-water nanoemulsion, containing superparamagnetic nanoparticles (magnetically polarizable) in the oil phase, are measured using the magnetic-chaining technique at different pH and salt concentrations. The role of mono-, di- and tri-valent salts on the inter-droplet force profiles are assessed. Force measurement studies reveal a lowering of inter-droplet spacing, within the linear chains, for higher salt concentrations due to an increased screening. Strong interfacial attachment of the charged nanoparticles results in the formation of an asymmetric charge cloud leading to an electric dipolar interaction. Incorporating the contributions of electric dipolar and screened Coulombic interactions, the theoretically estimated total repulsive force magnitudes are in good agreement with the experimental data. The obtained results offer better insights into the nature of colloidal force between charged particle stabilized nanoemulsions. [ABSTRACT FROM AUTHOR]

This study proposes a method for evaluating the axial decay length of the plasma pressure in detached helium plasmas with a fixed-point laser Thomson scattering and spectroscopic measurements in the linear divertor plasma simulator NAGDIS-II. By controlling the neutral gas pressure, the highly volume-recombining region called the “recombination front” was moved along the magnetic field. The differential terms for the electron pressure and the recombination-front position with respect to the neutral pressure were obtained. By using these two terms, the decay length of the plasma pressure was qualitatively calculated. In addition, from the movable Langmuir probe measurement, difference between the locally estimated decay length around the recombination front and the decay lengths over a wide axial range was discussed. The proposed method can be applied even in the huge heat flux condition where direct-contact measurements such as the Langmuir probe are not available.

Plasmonic waveguides are strategic compact structures consisting of nanoscale components and/or particles to carry the light. Here, by proposing a systematic and artificial configuration of fused nanoparticle assemblies, we develop an optothermally controllable plasmonic waveguide with high and tunable decay length for propagation of both singleand multimode waves. Using symmetric nanoplasmonic clusters based on phase-change material, here Ge2 Sb2 Te5, allowed us to efficiently control the beam propagation length and quality at the global telecommunication bands (λ ≈ 850 nm and λ ≈ 1550 nm). Employing both finite-difference time-domain and finite element method as numerical tools, we accurately computed the critical components of the proposed multifunctional plasmonic light carrier. We believe that the tailored subwavelength optical waveguide paves new approaches to develop practical advanced next-generation nanophotonic technologies. [ABSTRACT FROM PUBLISHER]

A model describing the frequency response of a quartz crystal microbalance (QCM) loaded with a single drop of liquid was established. The frequency shift of a QCM loaded with a single drop of liquid depends on only the effective mass layer instead of the total mass of the liquid droplet, and the effective mass layer is relevant to the droplet radius, the operating frequency of the QCM, and the density and viscosity of the liquid. In addition, a novel verification experiment was designed and performed, which indicated the validity of this model. [ABSTRACT FROM AUTHOR]

In flotation, bubble-particle attachment occurs when the wetting films of water formed in between are destabilized by collector coating. In most cases, DLVO forces are repulsive and hence stabilize wetting films; therefore, it is necessary to consider the role of attractive hydrophobic force as a destabilizer. In this regard, hydrophobic forces have been measured by monitoring dynamic profiles of an air bubble in nanoscale as it approaches a flat surface using the method described previously (Pan et al., 2011). The measurements conducted with gold substrates contacted in a 10 −5 M potassium ethyl xanthate (KEX) show that hydrophobic force increases with increasing contact time and water contact angle. After an excessively long contact time, hydrophobic force is found to decrease possibly due to multi-layer adsorption of xanthate. The forces measured from dynamic film profiles are in good agreement with those measured directly using a specially designed force apparatus. Analysis of the force data using the Frumkin-Derjaguin isotherm shows that bulk of the energy gained during bubble-particle interaction is due to the work done by the hydrophobic force at short range to overcome the repulsive van der Waals force. At long-range, hydrophobic force facilitates the kinetics of film thinning by reducing the force barrier created by double-layer force. [ABSTRACT FROM AUTHOR]