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Updated: Jun 12, 2025

Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees
Published on: November 29, 2016
Exciton-Phonon Coupling in Single ZnCdSe-Dot/CdS-Rod Nanocrystals with Engineered Band Gaps from Type-II to Type-I
Florian Johst1, Jannik Rebmann1, Hans Werners1
1Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, Hamburg D-20416, Germany.
Abstract:
Exciton-phonon coupling limits the homogeneous emission line width of nanocrystals. Hence, a full understanding of this is crucial. In this work, we statistically investigate exciton-phonon coupling by performing single-particle spectroscopy on colloidal Zn1- Cd Se/CdS and CdSe/CdS dot-in-rod nanocrystals at cryogenic temperatures (T ≈ 10 K). In situ cation exchange enables us to analyze different band alignments and, thereby, different charge-carrier distributions. We find that the relative intensities of the longitudinal optical S- and Se-type phonon replicas correlate with the charge-carrier distribution. Our experimental findings are complemented with quantum mechanical calculations within the effective mass approximation that hint at the relevance of surface charges.
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