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Updated: Apr 19, 2026

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Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
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Quantum-dot size and thin-film dielectric constant: precision measurement and disparity with simple models
Darcy D W Grinolds1, Patrick R Brown, Daniel K Harris
1Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
Nano Letters
|December 23, 2014
Abstract:
We study the dielectric constant of lead sulfide quantum dot (QD) films as a function of the volume fraction of QDs by varying the QD size and keeping the ligand constant. We create a reliable QD sizing curve using small-angle X-ray scattering (SAXS), thin-film SAXS to extract a pair-distribution function for QD spacing, and a stacked-capacitor geometry to measure the capacitance of the thin film. Our data support a reduced dielectric constant in nanoparticles.

