Ultrafast dynamics of excitons and charge carriers in semiconductor nanocrystals probed by femtosecond optical spectroscopy

December 12 2017
Types d’événements
Séminaire LSI
Elsa Cassette
Salle de réunion LSI, Bât.83, Ecole Polytechnique, Palaiseau
December 12 2017
from 10:30 to 12:00

The development of ultrathin two-dimensional (2D) semiconductor nanostructures have generated considerable interest over the past years. Among these nanostructures, colloidal semiconductor nanoplatelets have a thickness controlled with atomic precision (defined number of monolayers) which leads to strongly tunable and exceptionally narrow optical features [1]. The recent development of II-VI semiconductor heterostructures of various shapes and compositions has allowed to access new optical properties [1]. Here we use femtosecond transient absorption spectroscopy to study the ultrafast dynamics of excitons and charge carriers in CdSe-CdTe core-crown nanoplatelets [2].

We will also present the current progress in the development of a new two-dimensional electronic spectroscopy setup operating in the visible and ultra-violet range to investigate the sub-100 fs dynamics of colloidal nanocrystals after optical excitation well above the bandgap of the semiconductor nanostructures[3].


References :

[1] N. Nasilowski, B. Mahler, E. Lhuillier, S. Ithurria, B. Dubertret, Chem. Rev. 2016, 116, 10934.
[2] S. Pedetti, S. Ithurria, H. Heuclin, G. Patriarche, B. Dubertret, J. Am. Chem Soc. 2014, 136, 16430.
[3] E. Cassette, J.C. Dean, G.D. Scholes, Small 2016, 12, 2234.

Collaboration: Elsa Cassette1, Benoît Mahler2, Silvia Pedetti3, Gregory Scholes4

1) LIDYL, UMR 9222 CEA-CNRS-Université Paris-Saclay

2) LM, UMR 5306 Université Claude Bernard, Lyon 1 – CNRS

3) LPEM, UMR 8213 ESPCI-CNRS-UPMC, Paris V

4) Department of Chemistry, Princeton University, USA

IRAMIS/LIDYL