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Manipulation of the Spontaneous Emission Dynamics of Quantum Dots in 2D Photonic Crystals

A. Kress·F. Hofbauer·N. Reinelt·H. J. Krenner·R. Meyer·G. Boehm·J. J. Finley
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Abstract

We demonstrate the ability to control the spontaneous emission dynamics of self-assembled quantum dots via the local density of optical modes in 2D-photonic crystals. We show that an incomplete 2D photonic bandgap is sufficient to significantly lengthen the spontaneous emission lifetime ($>2\times$) over a wide bandwidth ($Δλ\geq40$ nm). For dots that are both \textit{spectrally} and \textit{spatially} coupled to strongly localized ($V_{mode}\sim1.5(λ/n)^{3}$), high $Q\sim2700$ optical modes, we have directly measured a strong Purcell enhanced shortening of the emission lifetime $\geq5.6\times$, limited only by our temporal resolution. Analysis of the spectral dependence of the recombination dynamics shows a maximum lifetime shortening of $19\pm4$. From the directly measured enhancement and suppression we show that the single mode coupling efficiency for quantum dots in such structures is at least $β=92%$ and is estimated to be as large as $\sim97%$.

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A. Kress, F. Hofbauer, N. Reinelt, H. J. Krenner, R. Meyer, G. Boehm, J. J. Finley. 2005-04-08. Manipulation of the Spontaneous Emission Dynamics of Quantum Dots in 2D Photonic Crystals. https://doi.org/10.1103/physrevb.71.241304

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