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arXiv · 0912.1365

Spectroscopy of 1.55 $μ$m PbS Quantum Dots on Si Photonic Crystal Cavities with a Fiber Taper Waveguide

M. T. Rakher·R. Bose·C. W. Wong·K. Srinivasan
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Abstract

We use an optical fiber taper waveguide to probe PbS quantum dots (QDs) dried on Si photonic crystal cavities near 1.55 $μ$m. We demonstrate that a low density ($\lesssim 100 μ$m$^{-2}$) of QDs does not significantly degrade cavity quality factors as high as $\approx3\times10^4$. We also show that the tapered fiber can be used to excite the QDs and collect the subsequent cavity-filtered photoluminescence, and present measurements of reversible photodarkening and QD saturation. This method represents an important step towards spectroscopy of single colloidal QDs in the telecommunications band.

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M. T. Rakher, R. Bose, C. W. Wong, K. Srinivasan. 2009-12-07. Spectroscopy of 1.55 $μ$m PbS Quantum Dots on Si Photonic Crystal Cavities with a Fiber Taper Waveguide. https://doi.org/10.1063/1.3396988

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