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Abstract: Nanowire arrays of zinc selenide with zinc blende structures have been synthesized on the zinc foil via a simple thermal evaporation route at relatively low temperature (∼400°C). A self-catalytic liquid–solid growth is proposed for the formation of the nanowires. The nanowires are usually 50–150nm in diameter, and several microns in length. Room-temperature cathodoluminescence spectrum from zinc blende ZnSe nanowires shows a near band edge emission band peaked at around 462nm and a broad deep-level emission band at around 580nm, respectively. [Copyright &y& Elsevier]

Hybrid surface wave propagation through the interface of semiconductor and metal waveguides consisting of CuO/Al and ZnO/Al have been investigated by numerical simulation due to their potential applications. COMSOL Multiphysics is used to simulate the waveguides by adjusting model properties. For the comparative study, the propagation constant (γ) , normalized phase (β) , attenuation constant (α) , propagation length (L) , total electric and magnetic energy propagated through the CuO-based Al waveguides and ZnO based Al waveguide is discussed. Comparative studies for both modifications were performed from 0 THz to 12 THz. This study employed boundary conditions to have the continuous behavior of the electric field component of hybrid surface waves (exhibits characteristics of both transverse waves and longitudinal waves) at the interface between metal and semiconductor. The ZnO-based modification shows a higher propagation constant (γ) at all frequencies. Similar trends are observed for propagation length (L) and propagation constant (γ). Meanwhile, the attenuation constant (α) of the CuO-based Al waveguide is higher than that of the ZnO-based Al waveguide. An identical trend was perceived for both electrical and magnetic energy. Maximum parameters favour the ZnO-based Al waveguide, which makes it superior to the CuO-based Al waveguide for high-frequency applications. • Hybrid surface wave propagation along the interface of CuO/Al and ZnO/Al was investigated. • An identical trend was perceived for both electrical and magnetic energy. • Maximum parameters favour the ZnO-based Al waveguide. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we report a simple novel approach to modulate the extinction spectra of P3HT/PMMA by manipulating the medium arrays on a substrate that is coated with self-assembled gold nanoparticles. The 20 nm gold nanoparticles were synthesized and then self-assembled on the APTMS/silicon substrate surface by immersing the substrate into the gold colloid suspension. A high-resolution P3HT/PMMA photoluminescent electron beam resist was used to fabricate various square hole arrays on the substrate containing gold nanoparticles. The P3HT/PMMA medium composition causes the blue shifts in the extinction peaks of up to 40.6 nm by decreasing the period from 500 nm to 200 nm for P3HT/PMMA square hole arrays with a diameter of 100 nm. The magnitude of blue shift is directly proportional to the product of the changes of medium refractive index and the array structure factor. These peak shifts and intensity of extinction spectra for various P3HT/PMMA medium arrays are well described by the finite-difference time-domain (FDTD) simulation results. Since this simple cost-effective technique can tune the extinction spectrum of medium and adding the gold nanoparticles can give more functionalities for sensing applications, such as surface-enhanced Raman scattering (SERS), that provides good opportunities for the design and fabrication of new optoelectronic devices and sensors. [Copyright &y& Elsevier]