Manipulation of the spontaneous emission dynamics of quantum dots in two-dimensional photonic crystals -: art. no. 241304

We demonstrate the ability to control the spontaneous emission dynamics of self-assembled quantum dots via the local density of optical modes in two-dimensional (2D) photonic crystals. We show that an incomplete 2D photonic band gap is sufficient to significantly lengthen the spontaneous emission lifetime (> 2x) over a wide bandwidth (Delta lambda >= 40 nm). For dots that are both spectrally and spatially coupled to strongly localized [V-modes similar to 1.5(lambda/n)(3)], high Q similar to 2700 optical modes, we have directly measured a strong Purcell-enhanced shortening of the emission lifetime >= 5.6x, limited only by our temporal resolution. Analysis of the spectral dependence of the recombination dynamics shows a maximum lifetime shortening of 19 +/- 4. From the directly measured enhancement and suppression we show that the single-mode coupling efficiency for quantum dots in such structures is at least beta=92% and is estimated to be as large as similar to 97%.