Metallic Photonic Crystal Slab Powerful Transmission And Low-dimensional Nanostructure Phonon Transport

The extraordinary high transmission of light through the metallic subwavelength hole array can be explained by the collaboration of localized Fabry-Perot waveguide resonances and the surface plasmon resonances. Based on the application of a tunable high pass filter and other optical devices at desired frequency, we design a thin metallic gold film with a periodic array of subwavelength holes in a certain frequency region. Due to their physical properties, and prospective and potential applications, the low-dimensional nanostructures and nanostructured materials, such as superlattices(SLs), quantum wells and wires , have been received increasing attentions and become one of the frontier research topics in condensed matter physics and material science in recent years. Simultaneously, rapid progress in the synthesis and processing of matericals with structures on nanometer length scales has created a demand for greater scientific understanding of the properties of nanoscale devices, individual nanostructures, and nanostructured materials. In this thesis, the enhanced transmission through a thin metallic gold film with a periodic array of subwavelength holes and the phonon transmission in the low dimensional nanostructures are investigated.We show that the enhanced transmission through a thin metallic gold film with a periodic array of subwavelength holes. These two different resonances, localized Fabry-Perot waveguide resonances and the surface plasmon resonances, can be characterized from normalized transmission spectra and the field distribution. The true nature of SP is studied with normalized zero-order transmission and the generated localized plasmons due to the (+1)-th and (-1)-th orders diffraction. The point-group theory analysis is used to characterize the two different resonances with several different structures.We study the phonon transmission and thermal conductance in a quantum waveguide with two stubs at low temperature using the scattering matrix method. The calculated results show that the threshold frequency of the onset of each phonon mode traveling through the quantum waveguide depends on the stub heights. The thermal conductance exhibits oscillatory decaying behaviour with the width between the two stubs due to the coupling effects between them. In addition, the transmission coefficient and thermal conductance are also sensitive to the widths and heights of the stubs.Finally, we investigate the effect of the cupped stubs on phonon transmission and thermal conductance in a nanowire at low temperature. The results show that the transmission coefficient of mode 0 depends on the height of the cupped stubs, and when the cupped stubs is high enough some wider stop-frequency gaps will appear since the cupped stubs enhance the phonon reflection. Moreover, the transmission coefficient and thermal conductance are more sensitive to the variation of the stub heigh and the width of the two cupped stubs for the nanowire with two cupped stubs than that of the nanowire with two gibbous stubs.