Femtosecond 1{ital P} -to-1{ital S} Electron Relaxation in Strongly Confined Semiconductor Nanocrystals
- Chemical Sciences and Technology Division, CST-6, MS-J585, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
High-sensitivity femtosecond transient absorption is applied to directly measure the population-depopulation dynamics of the lowest (1S ) and the first excited (1P ) electron states in CdSe nanocrystals (NC{close_quote}s) of different radii with 1S {emdash}1P energy separation up to 16longitudinal optical phonon energies. Instead of the drastic reduction of the energy relaxation rate expected due to a phonon bottleneck, we observe a fast subpicosecond 1P -to-1S relaxation, with the rate enhanced in NC{close_quote}s of smaller radius. This indicates the opening of new confinement-enhanced relaxation channels which likely involve Auger-type electron-hole energy transfer. {copyright} {ital 1998} {ital The American Physical Society}
- OSTI ID:
- 603134
- Journal Information:
- Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 18 Vol. 80; ISSN 0031-9007; ISSN PRLTAO
- Country of Publication:
- United States
- Language:
- English
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