A nanoscale Bragg grating reflector based on the defect metal-insulator-metal (MIM) waveguide is developed and numerically simulated by using the finite element method (FEM). The MIM-based structure promises a highly tunable broad stop-band in transmission spectra. The narrow transmission window is shown to appear in the previous stop-band by changing the certain geometrical parameters. The central wavelengths can be controlled easily by altering the geographical parameters. The development of surface plasmon polarition (SPP) technology in metallic waveguide structures leads to more possibilities of controlling light at deep sub-wavelengths. Its attractive ability of breaking the diffraction limit contributes to the design of optical sensors.

No abstract

In this paper, a metal–insulator–metal straight waveguide structure with quadrant ring resonators (QRRs) is theoretically presented. The transmission spectra at output ports are studied by the finite element method (FEM). The simulation results show great filtering effects at specific wavelengths. In order to unidirectionally control plasmonic flows at waveguide junctions, the original design has been expanded to T- and X-shaped waveguides with the QRRs. The results reveal that obvious Fano effects can be achieved in T-shaped systems.

2015): Plasmonic tunable filter based on trapezoid resonator waveguide, Journal of Modern Optics,The metal-insulator-metal waveguide structures coupled with a trapezoid cavity are proposed in theory. A variety of transmission features have been found from the simulation results, which is caused by the interference of the plasmonic modes in the trapezoid resonator. The transmission spectra can be effectively modulated by optimizing the geometrical parameters of our configurations such as the height, the upper and bottom edge lengths. Also, the coupling distance possesses great importance on the transmission characteristic. It is found that when the coupling distance is chosen to be around 20 nm, the filter works efficiently. When the trapezoid resonator is attached to the waveguide bus, the bandwidth becomes large. Besides, an effective band-stop filter can be achieved when the bottom edge length is large enough. The finite element method is carried out to verify our designs. We hope our work may open some new avenues for a high-performance plasmonic filter.

We investigate the dynamics of quantum coherence and quantum correlation of two qubits mediated by a one-dimensional plasmonic waveguide. The analytical expression of the dissipative dynamics of the two qubits is obtained for the initial X state. The dynamical behaviors of the quantum coherence and quantum correlation are shown to be largely dependent on the parameters of the initial state. Starting from a product state, quantum coherence and quantum correlation can be induced by the plasmonic waveguide. Under continuous drivings, steady quantum correlation can be obtained at specific distance larger than the operating wavelength and large values of steady quantum coherence are attainable at arbitrary distance. The detuning effect on the dissipation-driven generation of steady quantum coherence and quantum correlation is also explored.