Vibronic Excitons and Conical Intersections in Semiconductor Quantum Dots
Journal Article
·
· Journal of Physical Chemistry Letters
- Michigan State University, East Lansing, MI (United States); The Dow Chemical Company, Midland, MI (United States)
- Michigan State University, East Lansing, MI (United States)
- Stony Brook University, NY (United States)
- Middle Tennessee State University, Murfreesboro, TN (United States)
Surface defects and organic surface-capping ligands affect the photoluminescence properties of semiconductor quantum dots (QDs) by altering the rates of competing nonradiative relaxation processes. In this study, broadband two-dimensional electronic spectroscopy reveals that absorption of light by QDs prepares vibronic excitons, excited states derived from quantum coherent mixing of the core electronic and ligand vibrational states. Rapidly damped coherent wavepacket motions of the ligands are observed during hot-carrier cooling, with vibronic coherence transferred to the photoluminescent state. Furthermore, these findings suggest a many-electron, molecular theory for the electronic structure of QDs, which is supported by calculations of the structures of conical intersections between the exciton potential surfaces of a small ammonia-passivated model CdSe nanoparticle.
- Research Organization:
- Michigan State Univ., East Lansing, MI (United States); Michigan State University, East Lansing, MI (United States)
- Sponsoring Organization:
- National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- SC0010847; SC0021197
- OSTI ID:
- 2886435
- Alternate ID(s):
- OSTI ID: 1864694
- Journal Information:
- Journal of Physical Chemistry Letters, Journal Name: Journal of Physical Chemistry Letters Journal Issue: 39 Vol. 12; ISSN 1948-7185
- Publisher:
- American Chemical SocietyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Conical intersections shed light on hot carrier cooling in quantum dots
Journal Article
·
Sun Nov 30 19:00:00 EST 2025
· Journal of Chemical Physics
·
OSTI ID:3012974