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In this work, we theoretically investigate the strong coupling of Tamm Plasmon Polaritons (TPP) in a graphene/DBR/Ag hybrid structure. It is found that TPP can be generated at both upper graphene and lower Ag interfaces, which can strongly couple with each other, allowing strong light-matter interaction with dual-band perfect absorption. Numerical results reveal that resonance frequency of hybrid modes can be tuned by adjusting geometry parameters or dynamically modifying graphene Fermi energy. Coupling strength for the TPP hybrid modes exhibits a large tuning range, from large Rabi splitting to a very narrow induced transparency. The tunable TPP strong coupling with a dual-band perfect absorption in this simple layered system is potential in developing a broad range of graphene-based optoelectronic devices.

The usefulness of wavelet transforms has been compared and contrasted to Fourier transforms. Most importantly, wavelets transform provide a much needed alternative to Fourier transform for certain application such as pattern based monitoring and control. Effort has been made to provide a technique to extract essential trends from process signals and provide a compact representation. The effectiveness of a signal processing technique depends to a large extent on the nature of the signals involved. On technique that works for specific signal trends might not be effective in dealing with other signal trends. More so in pre-processing stage, signal extension has been identified as the critical factor influencing signal representation and retention of trends. This paper introduce a new algorithm in solving the present problems in sensor signal monitoring and control. The New Extension Technique (NET) was introduced, which provide an accurate wavelet decomposition irrespective of the nature of the signal. This method uses a statistical approach to provide a good approximation of the signal outside the boundaries of the signal depending on signal trends at the boundaries. Different statistical approaches were adopted for this purpose and four new extension methods were also introduced in order to ascertain which extension methods provide a reliable extension for all cases. The concept behind these methods is the same, since the signal samples close to the boundary are considered and a mean value is determined. The procedure for determining this mean value differs for each of these four methods; NET A, NET B, NET C, and NET D. The signal is then extended by making it symmetric with respect to that mean value and then inverting it.

We replace a commonly used Au film with an Au/Ag bimetallic film working as the sensing chip in the commercial surface plasmon resonance (SPR) instrument, Biacore 3000. The bimetallic chip gives out sharper SPR dip than that by the chip made of an Au film which can improve the sensitivity and accuracy. The applicability and stability of the bimetallic chip on the Biacore 3000 are tested by real-time monitoring of biological coupling processes between Sulfamethoxazole (SMX) and anti-SMX. The limit of detection of SMX is 1.8ng/ml.

The SPPs propagation on curved metal-dielectric interface is simulated by FDTD(finite-difference time-domain) method. The propagation loss, the transmittance and the reflection coefficients of SPPs on curved metal-dielectric interface with different radius of curvature is presented. The results shows the radiation loss is the key factor for the SPPs propagation when the propagation area is the same order as the wavelength, and the reflection coefficient is so small that it is ignorable. The critical situation when the radius is zero is also analyzed and the reflection coefficient is much larger than the former situation; for the transmittance, different electronic field components play different roles.

A new proposal for biological or microfluidic detection based on super-resolution near-field structure (Super-RENS) proposed by Tominaga is described. The mechanism of the near-field structure we proposed to image microfluid is very similar to near-field scanning optical microscope (NSOM). In this paper, we describe our simulation model and results of the electric field distribution in the near field zone and readout signals from the near-field structure to image microfluid. Calculations have demonstrated that the near-field structure can be applied in biomedicine to detect tracing element or image microfluid etc with a high spatial resolution beyond the diffraction limit.

The general role of the surface plasmons in the transmission of the metallic grating with narrow slits has been numerical described using the finite difference time domain method. Different parameters of grating have been used in the numerical simulation. It is concluded that whether the transmission peak of the SP resonance emerges or not does not depend on the SP travelling on the grating surface. The grating depth and the width of slit really give a dominant influence on the energy transmission for the SP resonance.

The optical reflector based on two-dimensional photonic crystal constructed by a square lattice of dielectric rods has already been reported in recent years, But the enormous difficulties to fabricate this structure are well-known, because the height of the rods must be finite in a real system so in this case no guided modes appears when air waveguides are created. On the contrary, there is not this inherent limitation for the photonic crystal waveguide made of air holes. In this paper, I will demonstrate an optical reflector based on photonic crystal,which constructed by air holes introduced into high index material. We design a monomode waveguide with even symmetry and discuss the characteristic of the reflector obtained by inserting several defects into the monomode waveguide in FDTD method.This kind of reflectors still have guided mode even if it possess finite thickness. This will make optical reflector based on two-dimensional photonic crystal nearer to practical application.

The interference of the surface plasmons polaritons (SPPs), localized SPPs, has been numerical analyzed by 2D finite difference time domain (FDTD) method. The near-field distributions of the localized SPPs have been presented. It is found that the quality of the output is not always good with strong interaction of the SPPs in super-RENS. It is also found that the near-field distribution and the output are almost changeless when the regions of the dark stripes have been adjusted.

We report the near-field investigation on azobenzene contained polymer films using scanning near-field optical microscopy. Nanometer scale dots and lines were inscribed on these films, and the topographies and transmitting images of these patterns could be obtained at the same time. The transmitting images were in agreements with the topographies, and it proved that trans-cis isomerization of the azobenzene moieties in the illuminated area induced both surface relief and anisotropy. The experimental results helped to discover the mechanism of the photo induced surface relief and anisotropy, and the agreement between the transmitting images and the topographies could be applied in pure optical writing/reading in high-density data storage.

In this paper, modified finite differential time domain (FDTD) method is used to investigate super resolution near-field structure (Super-RENS). The random distributed Ag particles, which is responsible for the localization and the enhancement of the surface plasmon within the Super-RENS, is included in this simulation. The near-field optical distribution when recording mark is just beneath the nonlinear aperture is achieved. And the transmitted readout signal is also simulated.

The very small aperture laser (VSAL) is an important light source used in the near-field optical storage system. It is necessary for studying the near-field property of VSAL's output light. The optical characters and the intensity distribution in the near-field of the output region of the VSAL have been numerical simulated using two dimension nonlinear FDTD (2D-NL-FDTD) method and the Fox-Li method. Through analyzing the results from the viewpoint of the Optics, the possible application in the near-field optical recording have been discussed, and some curves indicating the near-field optical characters of the output light have been presented.

The optical characters and light wave propagation of various fiber probes, solid immersion lens (SIL) system and Super-RENS for near-field optical recording are numerically simulated using 3D finite-difference time-domain (3D-FDTD) method in this paper. The aperture metal-coated probe have a near field spot size smaller than the bare-glass fiber probe, which means higher data density in near-field optical recording. The entirely metal coat probe is pointed out to have an extremely small near-field spot size about 10 nm, but the output electromagnetic wave propagation decrease to nearly zero within a few nanometers. The propagating and evanescent wave in different solid immersion lens (SIL) system is numerically simulated. The spot sizes are different because of different polarization. With the TbFe substrate, spot size will remain constant as observation distance z increased. But the propagating, evanescent and total energy decay more rapidly than the SIL system without TbFe substrate.