Wayne Yang

Structurally and materially sensitive hybrid surface plasmon modes in periodic silver-shell nanopearl and its dimer arrays

We numerically investigate the surface plasmon resonance (SPR) mode patterns in periodic silver-shell nanopearl arrays and its dimer arrays with the core relative permittivities filled inside the dielectric holes (DHs) by means of finite element method with three-dimensional calculations. Numerical results of resonant wavelengths corresponding to the effects of different period of unit cells, radii of DHs, illumination wavelengths, field propagation, electrical field stream lines, charge distributions, charge densities, half- body charge densities, and the DH core relative permittivities of periodic silver-shell nanopearls are also reported. It can be seen that the periodic silver-shell nanopearl arrays and its dimer arrays with DHs exhibit tunable SPR modes corresponding to the bonding and anti-bonding modes, respectively, that are not observed for the solid silver cases with the same volume. These results are crucial in designing localized SPR sensors and other optical devices based on periodic metal nanoparticle array structures.

Analysis of transmittance properties of surface plasmon modes on periodic solid/outline bowtie nanoantenna arrays

We numerically analyze the transmittance properties of the periodic outline bowtie nanoantenna arrays and examine the nanoantenna resonance conditions compared to their solid counterparts by means of finite element method. Simulation results show that the structural parameters may affect the nanoantenna resonance conditions, such as peak resonance wavelengths, propagation properties, and charge densities at spectral points of interest. Besides, the essences of transmittance spectra of the periodic solid/outline bowtie nanoantenna arrays corresponding to their bonding mode and anti-bonding mode are investigated as well.

Numerical Analysis on Birefringence of Photonic Crystal Fiber by Tuning Patterns and Infiltrating Materials of Innermost Air Holes

In this paper, we give a numerical analysis of a novel high-birefringence and low-confinement loss index-guiding photonic crystal fiber (PCF) using the finite element method by tuning patterns and filling the medium of innermost air holes. This PCF is composed of a solid silica core surrounded by six elliptical air holes and a cladding that consists of binary unit cells. The novelty of the proposed PCF structures is that the large elliptical air holes closest to the core have been rotated in different ways. Results show that the asymmetry in PCF cladding and the area of the PCF core are the key factors for determining the localization extent of the transverse mode. Modal birefringence values and confinement loss at the excitation wavelength of λ=1.55 µm can be easily achieved at a magnitude of the order of 10-2 and at less than 0.39 dB/km, respectively. From the viewpoint of numerical analysis, the effects of a material [with a refractive index <1 (i.e., a metamaterial)] on birefringence infiltrating into small (100–280 nm) innermost air holes, which are reported for the first time here, are also considered.

Near Field Properties and Plasmonic Effects of a Periodic Bowtie Antenna Array Embedded in a Substrate with Different Depths

 Abstract—We numerically investigate the near field properties and plasmonic effects of a periodic bowtie antenna array which is embedded in a substrate with different depths by means of finite element method with three-dimensional calculations. The electromagnetic modes obtained from the embedding cases are quite different from that of air background case of the same size, resulting in an intensity enhancement and a redshift phenomenon. We find that the embedded depth of the bowtie antenna in a silica substrate is an important parameter which can influence the field enhancement and the position of peak resonant wavelengths. The near-field intensity becomes less intense and the spectrum of peak resonances red-shifted as the embedded depth is increased.

Design of a small-displacement sensing system based on the surface plasmon resonance technology in heterodyne interferometry

In this paper, a small-displacement sensing system based on the surface plasmon resonance technology in heterodyne interferometry is proposed. The basic sensing unit is composed of a prism assembly and a displacement probe. The prism assembly is composed of a halfwave (λ/2) plate, two right-angle prisms and two rotation stages. In a prism assembly, two right-angle prisms are coated with 2Ti film and 45.5nm Au film. Thus, the surface plasmons are excited when a equals to a resonant angle αsp, αsp≈43.813°. In order to achieve the best resolution of the system, both of the initial incident angles are equal to 43.813° on the hypotenuse surfaces of two prisms. The small-displacement sensor is with high sensitivity and resolution due to the attenuated total reflection effect in heterodyne interferometry. Besides, we can obtain the results of the experiment in a distant place by using a ZigBee/Wi-Fi module. It can be found that the displacement resolution of the small-displacement sensor can reach 0.3nm at least by numerical simulation. The small-displacement sensor has some merits, e.g., easy operation, high measurement accuracy, high resolution and rapid measurement, etc.

Analysis of a Wide Spectral Range Plasmonic Outline Bowtie Antenna Ranging in 0.3-5.0 μM

We numerically analyze a broadband plasmonic outline bowtie antenna over a large parameter space by means of finite element method with three-dimensional calculation. The antenna is composed of a pair of triangular gold with outline shape placed in close proximity to each another. We show how the structural parameters affect the antenna resonance conditions, such as peak resonances wavelengths, electric field intensities, propagation properties, component field and total field distributions, charge densities and electrical filed stream lines at spectral points of interest. In addition, the characteristics of transmittance spectral of a periodic antenna array corresponding to the bonding mode and anti-bonding mode are investigated as well. Simulation results show that it is possible to tune an antenna with a constant length over a wide spectral range (ranging in 0.3–5.0μm or more range) while maintaining a constant antenna dimension, reduce the antenna footprint by a factor of 4.98, and increase the gap enhancement by 23%. This article has been removed from the website on January 3, 2013, because it has been found to violate plagiarism rule of our journal. Received 18 October 2012, Accepted 16 November 2012, Scheduled 7 December 2012 * Corresponding author: Yuan-Fong Chau (yfc01@uch.edu.tw).

Design of a Smart Green Energy Management System Based on DMX512 Protocol

In this paper, a smart green energy management system based on DMX512 protocol that is established by United States Institute for Theatre Technology (USITT) is proposed. The end user can monitor and control the LED lamps and electric powers according to the information received from the sensors by means of the channels of DMX512. In addition, the different color lights including red, green, and blue lights can be achieved by means of the color-mixing methods of red, green, and blue LEDs based on photometry theory. As a matter of fact, there have been attracted much attention on the mobile devices in recent years. In the study, a mobile device with an Android platform is used to control the electric power and LED lamps according to the information received from the ZigBee module immediately. However, the smart green energy management system based on DMX512 protocol has some merits, such as in real-time control, easy operation, low cost, etc.

Numerical investigation of series connection of nanoshells in plasmon waveguide

A two-dimensional plasmon waveguide in the form of rows of silver-shell nanorods distributed in a hexagonal lattice is proposed and compared to the solid-silver case. Transport of energy flow due to surface plasmon coupling is investigated using finite element method for visible range wavelengths. The proposed waveguide is divided into several sections with each section consisting of ten nanorods. Results show that the waveguide energy flow exhibits long-ranging propagation (>8 μm or more) by using series connection of each section, which plays the major role in coupling between them.

Analysis of four patterns of photonic crystal fibers with ultrahigh birefrigence

A High birefringence and low confinement loss of three patterns photonic crystal fibers (PCFs) are investigated and compared by using finite element method. Results show that the mode birefringence of proposed PCF with rectangular air holes at λ= 1.55 μm reaches 8.1 × 10-2 (which is the highest value to our knowledge) and the confinement loss is less than 5×10-3 dB/km, respectively. Besides, an ultrahigh birefringence up to 2.76 × 10-2 is also achieved from the proposed circular air holes PCF, which is the highest value compared to conventional circular air holes PCF.

A Compact 90° Bent Equal Output Ports of Photonic Crystal Beam Splitter with Complete Band Gap Based on Defect Resonance Interface

A compact 90 - bent equal output ports of photonic crystal (PC) beam splitter (BS) with complete band gap (CPBG) based on the efiect of defect resonance interface (DRI) in PC waveguides is designed and analyzed. The flnite-difierence time-domain method is adopted to simulate the relevant structures of defect mode in a two dimensional square lattice circular dielectric rods of anisotropic PC. The device size reduction and ∞exibility in polarization dependence compared with the conventional PCBS can be attributed to the same resonant frequency for both transverse-magnetic and transverse- electric polarization, because the PC structures designed here have a CPBG. The merit of our proposed PCBSs with identical lights at the output ports possess the short coupling length with direct coupling (the coupling length is the same as that of the width of DRI, 3a) and the short distance without cross-talk among the output ports (only three lattice constant, 3a), thus helping the design ∞exibility of the PCBSs in IOCs.