MODAL-ANALYSIS OF SPONTANEOUS EMISSION IN A PLANAR MICROCAVITY

A complete set of cavity modes in planar dielectric microcavities is p resented which naturally includes guided modes. We show that most of t hese orthonormal fields can be derived from a coherent superposition o f plane waves incoming on the stack from the air and from the substrat e. Spontaneous emission of a dipole located inside the microcavity is analyzed, in terms of cavity modes. Derivation of the radiation patter n in the air and in the substrate is presented. The power emitted into the guided modes is also determined. Finally, a numerical analysis of the radiative properties of an erbium atom located in a Fabry-Perot m ultilayer dielectric microcavity is investigated. We show that a large amount of light is emitted into the guided modes of the structure, in spite of the Fabry-Perot resonance, which increases the spontaneous e mission rate in a normal direction.