Resonant optical transmission through hole‐arrays in metal films: physics and applications

Extraordinary optical transmission through an array of holes in a metal film was reported by Ebbesen and coworkers in 1998. Since that work there has been abundant research activity aimed at understanding the physics and at the development of the many applications associated with this phenomenon, hence the topic of this review. The study of hole‐arrays in a metal is not new – theoretical contributions on a small‐hole array date back to Lord Rayleigh's description of Wood's anomaly in 1907 and there has been considerable research on metal meshes and hole‐arrays since 1962. Bethe's theory, adapted to treat hole‐arrays, is the simplest theoretical description of the transmission resonance. Following a description of this basic theory, we present the research on the additional effects from variations in real metal properties at different wavelengths, film thickness, hole‐shape and lattice configuration. The many promising applications being developed using hole‐arrays are examined, including polarization control, filtering, switching, nonlinear optics, surface plasmon resonance sensing, surface‐enhanced fluorescence, surface‐enhanced Raman scattering, absorption spectroscopy, and quantum interactions. Finally, the various approaches, developments in hole‐array fabrication, and integration of hole‐arrays into devices are described.