Exciton–Phonon Coupling in Single ZnCdSe-Dot/CdS-Rod Nanocrystals with Engineered Band Gaps from Type-II to Type-I
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 Zn<sub>1-<i>x</i></sub> Cd <sub><i>x</i></sub> Se/CdS and CdSe/CdS dot-in-rod nanocrystals at cryogenic temperatures (<i>T</i> ≈ 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.
Authors
- Christian Strelow (ORCID: https://orcid.org/0000-0002-5989-1675)
- Lars Klemeyer (ORCID: https://orcid.org/0000-0003-1103-8103)
- Jagadesh Kopula Kesavan (ORCID: https://orcid.org/0000-0002-0591-2493)
- Florian Johst (ORCID: https://orcid.org/0000-0002-7594-8440)
- Alf Mews (ORCID: https://orcid.org/0000-0001-5739-8820)
- Tobias Kipp (ORCID: https://orcid.org/0000-0002-9663-7422)
- Dorota Koziej (ORCID: https://orcid.org/0000-0002-9064-2642)
- Gabriel Bester (ORCID: https://orcid.org/0000-0003-2304-0817)
- Jannik Rebmann
- Hans Werners
Institutions
- Universität Hamburg (DE)
- Max Planck Institute for the Structure and Dynamics of Matter (DE)
- Hamburg Centre for Ultrafast Imaging
Publication Details
- Journal
- ACS Photonics
- Published
- 2024-09-06
- DOI
- https://doi.org/10.1021/acsphotonics.4c00931
- Citations
- 5
- Primary Topic
- Quantum Dots Synthesis And Properties
- Type
- article
- Field-Weighted Citation Impact
- 0.59
Funders
- Deutsche Forschungsgemeinschaft
- European Research Council