Observation of fast spontaneous emission decay in GaInAsP photonic crystal point defect nanocavity at room temperature

Abstract
The spontaneous emission decay in a photonic crystal slab nanocavity with a GaInAsP quantum well active region was measured at room temperature. Even far below lasing threshold, the decay was much faster than that for the as-grown wafer. A consideration including the enhanced spontaneous emission rate by the Purcell effect, intraband relaxation of carriers, nonradiative surface recombination, spatial hole burning, and carrier diffusion enabled us to explain different decay lifetime between on- and off-resonant conditions and between different size cavities. As a result, > 16 -fold shorter spontaneous emission lifetime was estimated, which strongly suggests the existence of a large Purcell effect.