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Updated: Nov 18, 2025
07:20
Trapping of Micro Particles in Nanoplasmonic Optical Lattice
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Van Hove Singularities and Trap States in Two-Dimensional CdSe Nanoplatelets
Nemanja Peric1, Yannick Lambert1, Shalini Singh2
1Université de Lille, CNRS, Centrale Lille, Université Polytechnique Hauts-de-France, Junia-ISEN, Centrale Lille, UMR 8520 - IEMN, F-59000 Lille, France.
Nano Letters
|February 5, 2021
Summary
Semiconductor nanoplatelets exhibit unique electronic properties due to their finite size. Peaks in their density of states reveal lateral confinement effects, differing from typical quantum wells.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Semiconductor nanoplatelets combine 2D semiconductor properties with colloidal synthesis.
- They serve as ideal platforms for studying semiconductor dimensionality effects.
Purpose of the Study:
- Investigate the conduction band density of states in individual CdSe nanoplatelets.
- Understand the lateral confinement effects in these nanostructures.
Main Methods:
- Low-temperature scanning tunneling spectroscopy.
- Tight-binding calculations.
Main Results:
- Observed peaks in the density of states, deviating from the expected steplike function of quantum wells.
- Identified deep trap states on the edge facets of the nanoplatelets.
Conclusions:
- The observed electronic structure rules out free in-plane electron motion.
- Findings provide insights into lateral confinement in finite-sized quantum wells.
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