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Sub-Wavelength Multi-Channel Imaging Using a Solid Immersion Lens: Spectroscopy of Excitons in Single Quantum Dots

K. P. Hewaparakrama·S. Mackowski·H. E. Jackson·L. M. Smith·G. Karczewski·J. Kossut
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Abstract

We demonstrate sub-wavelength imaging of excitons confined to single CdTe quantum dots. By combining slit-confocal microscopy with a hemispherical solid immersion lens we simultaneously map the emission of thousands of single quantum dots with a spatial resolution of 400 nm. By analyzing the linear polarization of the quantum dot emissions at B=0T, we find that the distribution of the exchange splitting is centered at zero with a standard deviation of 0.34 meV. Similar experiments performed at B=3T give an average value of the exciton effective g factor of 3.1. This experimental approach provides an effective means to gain statistical information about the quantum dot exciton fine structure in the ensemble.

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K. P. Hewaparakrama, S. Mackowski, H. E. Jackson, L. M. Smith, G. Karczewski, J. Kossut. 2004-08-25. Sub-Wavelength Multi-Channel Imaging Using a Solid Immersion Lens: Spectroscopy of Excitons in Single Quantum Dots. https://doi.org/10.1063/1.1829169

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