Abstract

In the field of quantum optics, the control of the radiative properties of single emitter through its coupling to a photonic structure has attracted great attention. In particular, optical cavities enable to reduce the radiative lifetime through the effect first discribed by Purcell. The Purcell factor, which is equal to the increase of the radiative decay rate, is proportional to the cavity quality factor Q and to the inverse of the modal volume V. Dielectric cavities characterized by high quality factor Q are widely used. However if the quality factor of the emitter is lower than Q then it replaces it in the Purcell formula. Thus increasing Q is useless. Another possibility is to use structures which exhibit very small modal volume such as plasmonic structures. They have low Q but, due to electromagnetic field localization at subwavelength scale, they are well suited for the control of semiconductor nanocrystals (NCs) radiative lifetimes since these NCs exhibit rather small quality factor at room temperature.

© 2011 IEEE