Experimental Solid State Group, Physics Department, Imperial College London, London SW72AZ, UK.
ACS Nano. 2010 Mar 23;4(3):1664-70. doi: 10.1021/nn901580r.
Subradiant and superradiant plasmon modes in concentric ring/disk nanocavities are experimentally observed. The subradiance is obtained through an overall reduction of the total dipole moment of the hybridized mode due to antisymmetric coupling of the dipole moments of the parent plasmons. Multiple Fano resonances appear within the superradiant continuum when structural symmetry is broken via a nanometric displacement of the disk, due to coupling with higher order ring modes. Both subradiant modes and Fano resonances exhibit substantial reductions in line width compared to the parent plasmon resonances, opening up possibilities in optical and near IR sensing via plasmon line shape design.
在同心环/盘纳米腔中观察到亚辐射和超辐射等离子体模式。亚辐射是由于母体等离子体的偶极矩的非对称耦合导致混合模式的总偶极矩整体减小而获得的。当通过纳米级的盘位移破坏结构对称性时，由于与高阶环模式的耦合，在超辐射连续体中出现多个 Fano 共振。与母体等离子体共振相比，亚辐射模式和 Fano 共振的线宽都有显著减小，这为通过等离子体线形状设计进行光学和近红外传感开辟了可能性。
