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arXiv · 1003.3346

Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide

Henri Thyrrestrup·Luca Sapienza·Peter Lodahl
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Abstract

We present measurements of the beta-factor, describing the coupling efficiency of light emitted by single InAs/GaAs semiconductor quantum dots into a photonic crystal waveguide mode. The beta-factor is evaluated by means of time-resolved frequency-dependent photoluminescence spectroscopy. The emission wavelength of single quantum dots is temperature tuned across the band edge of a photonic crystal waveguide and the spontaneous emission rate is recorded. Decay rates up to 5.7 ns^(-1), corresponding to a Purcell factor of 5.2, are measured and beta-factors up to 85% are extracted. These results prove the potential of photonic crystal waveguides in the realization of on-chip single-photon sources.

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Henri Thyrrestrup, Luca Sapienza, Peter Lodahl. 2010-03-17. Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide. https://doi.org/10.1063/1.3446873

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