Article (Scientific journals)
Ultrafast fs coherent excitonic dynamics in CdSe quantum dots assemblies addressed and probed by 2D electronic spectroscopy
Collini, Elisabetta; Gattuso, Hugo; Levine, R. D. et al.
2021In Journal of Chemical Physics, 154 (1), p. 014301
Peer reviewed
 

Files


Full Text
dotsjcp2021.pdf
Publisher postprint (4.62 MB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Abstract :
[en] We show in a joint experimental and theoretical study that ultrafast femto-second (fs) electronic coherences can be characterized in semiconducting colloidal quantum dot (QD) assemblies at room temperature. The dynamics of the electronic response of ensembles of CdSe QDs in the solution and of QD dimers in the solid state is probed by a sequence of 3 fs laser pulses as in two-dimensional (2D) electronic spectroscopy. The quantum dynamics is computed using an excitonic model Hamiltonian based on the effective mass approximation. The Hamiltonian includes the Coulomb, spin–orbit, and crystal field interactions that give rise to the fine structure splittings. In the dimers studied, the interdot distance is sufficiently small to allow for an efficient interdot coupling and delocalization of the excitons over the two QDs of the dimer. To account for the inherent few percent size dispersion of colloidal QDs, the optical response is modeled by averaging over an ensemble of 2000 dimers. The size dispersion is responsible for an inhomogeneous broadening that limits the lifetimes of the excitonic coherences that can be probed to about 150 fs–200 fs. Simulations and experimental measurements in the solid state and in the solution demonstrate that during that time scale, a very rich electronic coherent dynamics takes place that involves several types of intradot and interdot (in the case of dimers) coherences. These electronic coherences exhibit a wide range of beating periods and provide a versatile basis for a quantum information processing device on a fs time scale at room temperature.
Research center :
MolSys - Molecular Systems - ULiège
Disciplines :
Physical, chemical, mathematical & earth Sciences: Multidisciplinary, general & others
Author, co-author :
Collini, Elisabetta
Gattuso, Hugo ;  Université de Liège - ULiège > Département de chimie (sciences) > Laboratoire de chimie physique théorique
Levine, R. D.
Remacle, Françoise  ;  Université de Liège - ULiège > Département de chimie (sciences) > Laboratoire de chimie physique théorique
Language :
English
Title :
Ultrafast fs coherent excitonic dynamics in CdSe quantum dots assemblies addressed and probed by 2D electronic spectroscopy
Publication date :
2021
Journal title :
Journal of Chemical Physics
ISSN :
0021-9606
eISSN :
1089-7690
Volume :
154
Issue :
1
Pages :
014301
Peer reviewed :
Peer reviewed
European Projects :
H2020 - 766563 - COPAC - Coherent Optical Parallel Computing
Name of the research project :
MONACOMP
Funders :
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
CE - Commission Européenne [BE]
Available on ORBi :
since 26 January 2021

Statistics


Number of views
38 (4 by ULiège)
Number of downloads
2 (2 by ULiège)

Scopus citations®
 
10
Scopus citations®
without self-citations
3
OpenCitations
 
6

Bibliography


Similar publications



Contact ORBi