Optical Nanorod Antennas Modeled as Cavities for Dipolar Emitters: Evolution of Sub- and Super-Radiant Modes

TIM H. TAMINIAU; FERNANDO D. STEFANI; NIEK F. VAN HULST

NANO LETTERS (PRINT)

AMER CHEMICAL SOC

Año: 2011 vol. 11 p. 1020 - 1024

1530-6984

Optical antennas link objects to light. Here we derive an analytical model for the interaction of dipolar transitions with radiation through nanorod antenna modes, by modeling nanorods as cavities. The model includes radiation damping, accurately describes the complete emission process, and is summarized in a phase-matching equation. We analyti- cally discuss the quantitative evolution of antenna modes, in particular the gradual emergence of subradiant, super-radiant, and dark modes, as antennas become increasingly more bound, i.e., plasmonic. Our description is valid for the interaction of nanorods with light in general and is thus widely applicable.