0469144 - ÚFP 2017 RIV GB eng J - Článek v odborném periodiku
Lenngren, N. - Abdellah, M.A. - Zheng, K. - Al-Marri, M.J. - Zigmantas, D. - Žídek, Karel - Pullerits, T.
Hot electron and hole dynamics in thiol-capped CdSe quantum dots revealed by 2D electronic spectroscopy.
Physical Chemistry Chemical Physics. Roč. 18, č. 37 (2016), s. 26199-26204. ISSN 1463-9076. E-ISSN 1463-9084
Institucionální podpora: RVO:61389021
Klíčová slova: quantum dots (QDs) * two-dimesional coherent spectroscopy * carrier relaxation * carrier trapping
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 4.123, rok: 2016 ; AIS: 1.124, rok: 2016
DOI: https://doi.org/10.1039/c6cp04190f

Colloidal quantum dots (QDs) have attracted interest as materials for opto-electronic applications, wherein their efficient energy use requires the understanding of carrier relaxation. In QDs capped by bifunctional thiols, used to attach the QDs to a surface, the relaxation is complicated by carrier traps. Using 2D spectroscopy at 77 K, we follow excitations in thiol-capped CdSe QDs with state specificity and high time resolution. We unambiguously identify the lowest state as an optically allowed hole trap, and identify an electron trap with excited-state absorption. The presence of traps changes the initial dynamics entirely by offering a different relaxation channel. 2D electronic spectroscopy enables us to pinpoint correlations between states and to easily separate relaxation from different starting states. We observe the direct rapid trapping of 1S3/2, 2S3/2, and 1S1/2 holes, and several competing electron relaxation processes from the 1Pe state.
Trvalý link: http://hdl.handle.net/11104/0267008