The surface polariton splitting due to thin surface film LO vibrations

The influence of thin dielectric (LiF) films on the sapphire and rutile surface polaritons has been investigated by the attenuated total reflection technique. It is shown that the LO oscillation of the 100 Å LiF film causes a splitting in the minimum of the surface polariton ATR reflectivity. This splitting is the larger, the larger the film thickness is.     

Surface phonon frequencies for magnesium oxide

Surface phonon branches and the surface excess distribution of frequencies f^S(ω) have been calculated for the (001) face of MgO with a rigid shell model for a fifteen-layer film. Comparison with the f^S(ω) obtained by Rieder and Hörl from neutron scattering shows agreement with some features as well as the need for further experimental work.     

Nonlinear Goos-Hänchen shifts due to surface polariton resonance in Kretschmann configuration with a Kerr-type substrate

As the surface polaritons are excited in Kretschmann configuration with a Kerr-type substrate, the nonlinear Goos-Hänchen (GH) shifts exhibit the optically hysteretic response to the intensity of incident light. For thicker metal films, the GH shifts become very sensitive to the intensity of incident light and the angle of incidence.     

Phonon‐polariton entrapment in homogenous surface phonon cavities

Surface phonon cavities that are homogenous in both mechanical and dielectric properties are reported. The cavities are formed by the placement of a defect of a single domain within periodic domain inversion of single crystal piezoelectric lithium niobate that exhibits surface phononic bandgap through the phonon‐polariton coupling. Surface cavity resonances are observed within the bandgap, which manifest in entrapment of phonon‐polariton within the defect. In addition to demonstrating that the observed resonances are non‐radiative and decoupled to bulk radiation, which is critical for high Q cavities, it is also shown the possibility to tune the surface cavity resonance spectra simply by varying the defect width. Such an ability to excite surface cavity resonance that is non‐radiative with simultaneous localization of the electric field together with the advantage of a cavity that is physically formed from a completely monolithic and uniform material offers unique opportunities for widespread applications for example in actuation, detection, and phonon lasing that can be fully integrated with other physical systems such as quantum acoustics, photonics, and microfluidics.

     

Thermally driven sensitive surface phonon polariton modes in thin-film SiC

The results of this work show that significant changes to the spectral properties of thermal emission may be accomplished by taking advantage of surface phonon polariton (SPP) modes that are very sensitive to small refractive index changes. Surface phonon polaritons are interface restricted wave modes that do not usually participate in thermal radiative energy exchange. In this work, the possibility of varying the spectral properties by using a thin-film surface active material, layered between dielectrics, is explored. Unlike surface gratings, the multilayered structure discussed in this work couples the surface modes into radiative modes using subtle changes in refractive index. The proposed multilayer effect is studied by first developing the SPP mode dispersion relation to identify the spectral location of the surface modes. The relationship between SPP coupling and refractive index change is then developed. The fluctuation-dissipation theorem and an impedance boundary condition is used to theoretically show how thermal radiation can excite SPP modes. Results are then presented that show how film thickness and substrate properties act to support SPP modes that are particularly sensitive to changes in refractive index and therefore offers opportunities for dramatic changes to the spectral properties.     

Fluorescence spectrum due to surface plasmon polariton emission in a three level atom

The dynamics of a V-type three level atom positioned inside a metallic slab sandwiched between two asymmetric infinite dielectrics is studied. The surface plasmon polaritons supported by this structure are calculated, quantized and their dispersions are found to exhibit plasmonic band gaps which in turn modify the spontaneous transition rates and the fluorescence spectrum. Interesting features arise from the variations of the decay rate and spectrum with the mode frequency and electron density including local field effects.     

Adsorption of nitrogen oxide molecules to the surface of nanosized nickel clusters formed on the (111) surface of a magnesium oxide film

The properties of the systems formed on deposition of Ni atoms on the (111) surface of a MgO film of thickness equal to six monomolecular layers grown on a Mo(110) crystal face and the adsorption of NO nitrogen oxide molecules to the system surface have been studied by methods of electron spectroscopy (AES, XPES, LEED, LEIBSS) and reflective infrared absorption spectroscopy. On deposition of Ni atoms on the surface of MgO at a substrate temperature of 600 K, three-dimensional islands of Ni are formed. The subsequent adsorption of NO results in molecule dissociation even at 110 K. The efficiency of this process depends on the morphology of the Ni layer.     

Far-infrared optical absorption due to surface phonon excitations in small metal particles

In this paper, the role played by the excitation of surface phonons in the far infrared optical absorption of small metallic spheres is explored. We find that for frequencies ranging between 100 cm^-3 and 200 cm^-1 this absorption mechanism is dominating over the ones coming from considering electronic excitations or the Joule heating.     

New mechanism of surface polariton resonance at an isolated interface between transparent dielectric media (non-Tamm quasistationary surface polariton states)

A system of quantum dots on the basis of Al_xIn_1-xAs/Al_yGa_1-y As solid solutions has been studied. The usage of broadband Al_xIn_1-x solid solutions as the basis of quantum dots makes it possible to expand considerably the spectral emission range into the short-wave region, including the wavelength region near 770 nm being of interest for the design of aerospace systems of quantum cryptography. The optical characteristics of single Al_xIn_1-xAs quantum dots grown according to the Stranski–Krastanov mechanism are studied by the cryogenic microphotoluminescence method. The fine structure of exciton states of quantum dots is studied in the wavelength region near 770 nm. It is shown that the splitting of exciton states is comparable with the natural width of exciton lines, which is of great interest for the design of emitters of pairs of entangled photons on the basis of Al_xAs_1-x quantum dots.     

Free space optical beam coupled to surface plasmonic polariton waves via designed grooves in metal film

Surface plasmonic polariton(SPP) waves with complicated wavefronts have important implications in nanophotonic sciences and applications. The surface electromagnetic wave holography method is applied to designed grooves on a metal surface for coupling a plane wave in free space to complicated wavefront SPP waves.The grooves illuminated by the plane wave incident from free space serve as secondary SPP waves sources, that radiate cylindrical SPP waves. New controllable wavefronts originate from these secondary SPP waves interfering with each other, based on the Huygens–Fresnel principle. Several applications of the method are demonstrated, such as converting coupling waves in free space into focusing SPP waves on a metal surface.     

Efficient use of the surface plasmon polariton resonance in light scattering from adsorbates

Efficient collection of the scattered light from adsorbates on silver in the attenuated total reflection configuration is demonstrated with a so-called Weierstrass prism. The Raman signal from carbon contamination on silver films is enhanced by two orders of magnitude with respect to the simple external backscattering configuration.     

Coupled surface polariton with guided wave polariton modes in asymmetric metal clad dielectric waveguides

It is emphasized that in metal-dielectric layered systems with a thin metallic layer, surface plasmon-polaritons (SP) can couple with guided wave polaritons (GWP) and form new hybrid modes with properties of both SP and GWP. This is illustrated by analyzing the properties of electromagnetic modes in an asymmetric metal-clad-dielectric-slab waveguide and their dependence on the thickness of metal cladding.     

Polarization stokes polarimetry of the amplitude and phase characteristics of surface plasmon polariton resonance

The amplitude and phase characteristics of internal reflection of gold nanofilms have been investigated using polarization modulation of electromagnetic radiation in the Kretschmann geometry. The component Q (the difference between the reflection coefficients R _s ² and R _p ² for the s and p polarizations, respectively) and the component V of the Stokes vector (the difference between the phases of the orthogonal components of linearly polarized radiation) of light reflected from a half-cylinder of the total internal reflection with gold films of different thicknesses on its flat surface have been measured as a function of the angle of incidence of light in the wavelength range 500–1000 nm. It has been demonstrated that, in the range of parameters corresponding to the manifestation of the plasmon polariton resonance (the angle of incidence of light, the wavelength, the metal film thickness), the dispersions of the amplitude and phase characteristics are in quantitative and qualitative agreement with the model concepts of a classical oscillator.     

Spin relaxation due to polar optical phonon scattering

Spin relaxation due to polar optical phonon scattering in semiconductors was investigated. The relaxation of the electron spin was found to increase with increasing the strength of the electric field. However, a high field completely depolarized the electron spin due to an increase of the spin precession frequency of the hot electrons, suggesting that high field transport conditions might not be desirable for spin-based technology with these semiconductors. It was also found that spin relaxation decreases with increasing moderately n-doping density or decreasing temperature. The results were discussed in comparison with the data available in the literature.     

半壳结构金纳米膜的局域表面等离子体共振效应

采用纳米模版印刷术和化学自组装技术制备了半壳结构的金粒子膜.利用场发射扫描电子显微镜和光谱仪等测试手段对样品的结构和光学性质进行了分析.研究发现，该结构的金膜所具有独特的局域表面等离子体共振效应取决于样品的粒子大小、间距等微观结构，且其峰值吸收波长对其周围环境介质的介电常数变化十分敏感.实验结果表明，粒子排列均匀的亚单层膜结构是控制光学性质稳定的关键. 关键词： 局域表面等离子体共振 半壳结构 纳米模版印刷术     

Propagation of femtosecond surface plasmon polariton pulses on the surface of a nanostructured metallic film: space-time complex amplitude characterization

Ultrashort surface plasmon polariton (SPP) pulses, propagating on the surface of a nanostructured metallic film, are characterized in space and time using time-resolved spatial-heterodyne imaging. Optical pulses are coupled from free space into various surface modes using a 2D array of circular nanoholes, and spatial amplitude and phase characteristics of the scattered surface field are measured with femtosecond-scale time resolution. Demonstrated in-plane focusing of SPP pulse provides additional electromagnetic field localization with possible applications in SPP nanophotonics, nonlinear surface dynamics, biochemical sensing, and ultrafast surface studies.     

Influence of surface roughness on surface plasmon resonance phenomenon of gold film

We experimentally investigate the effects of the surface roughness of gold thin films on the properties of surface plasmon resonance. By annealing at different temperatures, film samples with different surface morphologies are obtained. Specifically, due to the diffusion of the gold atoms towards the films3 surface, the surface rootmean-square roughness decreases with the increasing annealing temperature. Then, we measure the surface plasmon resonance of the samples. The results show that the resonance angle of the surface plasmon resonance is sensitive to the root-mean-square roughness, and it gradually decreases by reducing the surface root-mean-square roughness.Yang