arXiv subjects

Qian-jin Wang

Publications and source records attributed to Qian-jin Wang.

5 recordsLinked to original sources

arXiv2009

Long-Wavelength Optical Properties of a Plasmonic Crystal

The long-wavelength optical properties of a plasmonic crystal composed of gold nanorod particles have been studied. Because of the strong coupling between the incident light and vibrations of free electrons, bulk polariton excitation can be induced and a polaritonic stop band will be created. An analytical model has been established,which was confirmed by the numerical simulations. The similarity between the plasmonic and ionic crystals, as well as various optical properties, may be of both fundamental and practical interests.

cond-mat.mes-hall↗

arXiv2009

Splitting of transmission peak due to the hole symmetry breaking

We studied experimentally and theoretically the optical transmission through asymmetrical holes of a metal film, which is constructed by introducing small protuberances to the sides of individual square holes. Due to the symmetry breaking of hole shape, an interesting transmission feature appears: both the Ag-glass (1, 0) and Ag-glass (1, 1) peaks split distinctly. Detailed studies indicate that the peak splitting is actually associated with the two asymmetrical waveguide surface-plasmon (WSP) modes confined on the surface of opposite hole walls. The finding demonstrates the crucial role of WSP modes and enriches our understanding of the phenomenon.

physics.optics↗

arXiv2009

Transmission resonance in a composite plasmonic structure

The design, fabrication, and optical properties of a composite plasmonic structure, a two-dimentional array of split-ring resonators inserted into periodic square holes of a metal film, have been reported. A new type of transmission resonance, which makes a significant difference from the conventional peaks, has been suggested both theoretically and experimentally. To understand this effect, a mechanism of ring- resonance induced dipole emission is proposed.

physics.optics↗

arXiv2009

Light reflection from a metal surface with subwavelength cavities

The interaction of light with the localized/delocalized system, i.e., a metal surface with rectangular cavities of finite depth, has been studied. Reflection spectrum has been measured in the optical frequencies and resonant minima have been observed. We have developed an analytical model, which agrees well with the experiment. The localized waveguide resonance and delocalized surface resonance have been identified and discussed. The results may be useful for manipulating the coupling between light and matters.

physics.optics↗

arXiv2007

Dual effect of surface plasmons in light transmission through perforated metal films

The light transmission through square and rectangular holes in a metal film has been studied. By taking account of plasma response of real metal on hole walls as well as metal surface, an analytical result for the transmission has been deduced, which agrees well with the experiments. We show that the light transmission involves both the diffraction modes and the surface plasmons. Strong coupling of diffraction modes to surface plasmon polariton results in the transmission minima, whereas the coupling to cavity surface plasmon leads to the transmission maxima. The results suggest a dual-effect of the surface plasmons.

physics.optics↗