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Surface plasmon polaritons are electromagnetic surface waves coupled to electron plasma oscillation of metals at a metal-dielectric interface. At optical frequencies, these modes are of great interest because of their high confinement to a metal-dielectric interface. Due to the field enhancement at the interface, they have been used in different applications such as sensors, second harmonic generation and enhanced Raman scattering. Surface plasmon resonance based sensors are being used for detection of molecular adsorption such as DNA and proteins. These sensors are known to be highly sensitive and have successfully become commercialized. Terahertz (THz) frequency band of electromagnetic spectrum has attracted researchers in the last few years mostly because of sensing and imaging applications. Many important chemical and biological molecules have their vibrational and rotational resonance frequencies in the THz range that makes the THz sensing one of the most important applications of THz technology. Considering above mentioned facts, extending the concept of surface plasmon sensors to THz frequencies can result in sensitive sensors. In this work the possibility of this extension has been investigated. After reviewing optical surface plasmon polariton waves and a basic sensor configuration, surface plasmon polariton waves propagating on at metallic and doped semiconductor surfaces have been examined for this purpose. It has been shown that these waves on metallic surfaces are loosely confined to the metal-dielectric interface and doped semiconductors are also too lossy and cannot meet the requirements for sensing applications. Afterwards, it is shown that periodically patterned metallic surfaces can guide surface waves that resemble surface plasmon polariton waves. A periodically patterned metallic surface is used to guide THz surface plasmon polariton-like surface waves and a highly sensitive sensor is proposed based on that. The quasi-optical continuous wave (CW) THz radiation is coupled to this structure using the Otto's attenuated total reflection (ATR) configuration and the sensitivity of the device is discussed. A general scattering parameter based model for prism coupling has been proposed and verified. It is shown that a critical coupling condition can happen by changing the gap size between the prim and periodic surface. Details of fabrication of the periodic structure and experimental setup have also been presented.

Surface plasmon polaritons are electromagnetic surface waves coupled to electron plasma oscillation of metals at a metal-dielectric interface. At optical frequencies, these modes are of great interest because of their high confinement to a metal-dielectric interface. Due to the field enhancement at the interface, they have been used in different applications such as sensors, second harmonic generation and enhanced Raman scattering. Surface plasmon resonance based sensors are being used for detection of molecular adsorption such as DNA and proteins. These sensors are known to be highly sensitive and have successfully become commercialized. Terahertz (THz) frequency band of electromagnetic spectrum has attracted researchers in the last few years mostly because of sensing and imaging applications. Many important chemical and biological molecules have their vibrational and rotational resonance frequencies in the THz range that makes the THz sensing one of the most important applications of THz technology. Considering above mentioned facts, extending the concept of surface plasmon sensors to THz frequencies can result in sensitive sensors. In this work the possibility of this extension has been investigated. After reviewing optical surface plasmon polariton waves and a basic sensor configuration, surface plasmon polariton waves propagating on at metallic and doped semiconductor surfaces have been examined for this purpose. It has been shown that these waves on metallic surfaces are loosely confined to the metal-dielectric interface and doped semiconductors are also too lossy and cannot meet the requirements for sensing applications. Afterwards, it is shown that periodically patterned metallic surfaces can guide surface waves that resemble surface plasmon polariton waves. A periodically patterned metallic surface is used to guide THz surface plasmon polariton-like surface waves and a highly sensitive sensor is proposed based on that. The quasi-optical continuous wave (CW) THz radiation is coupled to this structure using the Otto's attenuated total reflection (ATR) configuration and the sensitivity of the device is discussed. A general scattering parameter based model for prism coupling has been proposed and verified. It is shown that a critical coupling condition can happen by changing the gap size between the prim and periodic surface. Details of fabrication of the periodic structure and experimental setup have also been presented.

Electron-excited surface plasmon resonance (eSPR) is investigated for potential use in biosensors. Optical SPR sensors are commercially available at present and these sensors are extremely sensitive, but have the tendency to be relatively large, expensive, and ignore the potentials of microelectronic technology. By employing the use of various microelectronic and nanotechnology principles, the goal is to eventually design a device that exploits the eSPR phenomenon in order to make a sensor which is siginificantly smaller in size, more robust, and cheaper in cost.

In recent years, the Surface Plasmon Polariton effect has played an important role for entering the Nano-world. When the metallic materials reach the nanometer level, many special characteristics show up. As the progress of advanced technology development, the equipments which can be operated in nano grade level are more stabilized. Many special surface Plasmonic properties have been discovered through the measurements. This research is to focus on using the Surface Plasmon coupling to excite colloidal quantum dots and observing the emissive behavior of quantum dots. The experiments of changing the distance between the quantum dots and the metal film were performed. The blinking effect disappeared when the quantum dots are very close to the metal film. It showed that some other mechanism is competing with Auger recombination in the quantum dots. The lifetime modification and emission intensity were measured when one quantum dot was placed near a silver cube. The coupling between the surface Plasmon polariton and the quantum dot was discussed.

This study is to investigate that the polishing behavior will be independent of or dependent on the direction of particle motion by the anisotropic polishing phenomenon of hydrodynamic polishing process under the semi-contact lubricating condition. There are two types of experiments to be examined to get to the objectives. First, taking polishing on the work surface which possesses the isotropic surface roughness, to discuss the variation of the smoothing efficiency of the surface irregularities in the five different directions on the work surface. Second, taking three kinds of polishing, ¡§longitudinal, transverse, and oblique roughness polishing¡¨, on the work surface which possesses the anisotropic surface roughness. Then to discuss the variation of the smoothing efficiency of the surface irregularities on the work surface. Both the results of two types experiments should be take to distinguish the difference between one smoothing efficiency and the others from using the hypothesis testing. All hypothesis tests about the experiment results of the work piece which possesses the isotropic surface roughness are accepting . But, most hypothesis tests about the experiment results of the work piece which possesses the anisotropic surface roughness are rejecting . The theory analysis about the smoothing efficiency is discussing. The discussion about the smoothing efficiency can explain the phenomenon due to taking polishing on the work surface which possesses the anisotropic surface roughness. The reason why the phenomenon happened is possible the effects of different lubrication condition. Last, from the lubrication theory, the effects of different lubrication condition due to different surface texture can be employed to verify the explanation about the phenomenon is suitable. The conclusion from the experiment results and the theory analysis is: the polishing behavior is possible independent of the direction of particle motion by the anisotropic polishing phenomenon of hydro- dynamic polishing process under the semi-contact lubricating condition.

ABSTRACT This research uses Taguchi Method, combined with Computer Aided Design and Manufacturing, processing the work piece into the saddle type. Next, diverse sampling methods are applied to measure the profile of surface with Coordinate Measuring Machine, with an aim to analyzing the main factors that influence cutting and seeking the last conditions for cutting out the curved surface; in addition, I will probe into the contribution rate of each factor which influences the precision during the process of measurement. The following results of this research are expected to be offered to the circles of vocational education as a basis of processing and measuring instruction. In this way, it will not take too much time to try and error and therefore, the practice course can be more efficient. 1. With reference to the documents that are focused on the factors affecting the cutting, this thesis, by means of Taguchi Method, shows that during the process of cutting saddle-type curved surface, the rotating speed of the axle is the most influential, whose contribution rate is 59.38%. 2. Since most documents are on circles, balls or cone objects, this thesis will aim at the measurement of saddle-type curved surface, with an intention to further the measuring technique. 3. It is found that as to the saddle-type curved surface, random sampling can get the profile of surface with minimal errors, and has no such trouble as using HSS or LHS, which can reduce time and cost. 4. In the experiment of Taguchi Method, according to analysis of variance, the influence of the sampling area is the greatest while the choice of sampling method only contributes to 3.46%.

The ultimate value of surface roughness and its characteristic for the polishing process was investigated in this thesis. To find out the nature of ultimate surface roughness by means of the hydrodynamic polishing process and can be used for all polishing method. A preliminary mathematical model that was proposed to explain the ultimate surface roughness proceedings and a series of experiments was planed to verify suitable of this model. Starting with the rule for ultimate surface roughness happened. The assumption that abrasive particle at roughness peak and valley machining capability differ less than one atom, the ultimate surface roughness be attained. We can propose the mathematical model of ultimate surface roughness based on this rule and the previous study of hydrodynamic polishing process. Following by useing the computer simulation to help us exploring ultimate surface roughness characteristic and testing experiments fit for the forecasting. Finally, we explain reasons that cause the experiment results not agree with the model anticipation and propose better lubrication condition to polish the optimum surface.

Surface Laser Light Scattering (SLLS) is a heterodyne detection technique used to probe the surface properties of fluid interfaces. These interfaces are either liquid/liquid or vapor/liquid, and they may include insoluble monolayers or polymer films deposited on liquid surfaces as well as microemulsions in solution at low concentration. This technique provides one with a nonperturbative way to obtain surface tension and viscosity. A diffraction grating is employed to provide a stable local oscillatior, hence selecting an accurate ripplon wave vector . This thesis deals with the investigation of the interface between air and solution consisting of the methanol and water mixture and poly(N-isopropylacrylamide) or PNIPAM which is one of the fascinating polymeric materials. The polymer PNIPAM shows distinct responses to variations in the surrounding environment (such as thermal gradient, change in pH, etc.). The surface tension extracted from the SLLS data using the Kelvin equation is found to agree well with that obtained by using the Wilhelmy plate method. For the range of wave vectors cm-1, the power spectrum detected in frequency domain can be fit to a Lorentzian profile. Our experiments show that when the volume percentage of methanol increases, the interfacial property becomes insensitive to the presence of PNIPAM.

Abstract The occurrence of ripples on the workpiece surface after solidification in electron-beam weld or melting is experimentally and analytically investigated. The maximum accelerating voltage and welding current of electron-beam welder are 60kV and 50mA, respectively, while the workpieces are four different materials containing different quantities of sulfur. Using a scale analysis to account for heat transfer and fluid flow induced by different quantities of surface active element in the molten pool. The result predicted results show good agreement with experimental data.