Abstract
In transient absorption (TA) spectra, the bleach features originating from state filling are overlapped by their energy-shifted derivatives, arising from excited state energy level shifts. This makes the direct extraction of carrier dynamics from a single-wavelength time-trace misleading. Fitting TA spectra in time, as Gaussian functions and their derivative-like shifted Gaussians, allows to individually extract the real dynamics of both photobleached transitions, and their energy shifts. In CdTe nanorods (NRs) we found a delayed heating of holes due to the release of the large excess energy in the electron relaxation process. The slow hole-trapping process is consistent with a high number of surface trap states in these model NRs. Our results show that only a correct disentanglement of bleaching and energy shift contributions provides a reliable framework to extract the underlying carrier relaxation dynamics, including trapping, non-radiative recombination, and eventually carrier multiplication. (C) 2015 Elsevier B. V. All rights reserved.
Item Type: | Journal article |
---|---|
Faculties: | Physics |
Subjects: | 500 Science > 530 Physics |
ISSN: | 0301-0104 |
Language: | English |
Item ID: | 47696 |
Date Deposited: | 27. Apr 2018, 08:13 |
Last Modified: | 07. May 2024, 18:42 |