Coherent spectroscopy in strongly confined optical fields

A single emitter is usually expected to have a weak effect on a light beam. However, recent experiments have shown that up to 12% of the incident power can be extinguished in the forward direction if it is focused or confined by a small aperture. To explore the theoretical limits of the effect of a single emitter on a stream of photons, we investigate the interaction of a single oscillating dipole with tightly confined optical fields and demonstrate that light can be attenuated even by 100% under appropriate conditions. These findings are not only interesting for applications in spectroscopy and sensing, but also open doors for information processing at the nanometer scale.