Premium
Excitons in a perfect quasi‐1D organic quantum wire, an isolated polydiacetylene chain
Author(s) -
Legrand Laurent,
Choueiry Antoine Al,
Holcman Jérémy,
Enderlin Alexandre,
Melet Romain,
Barisien Thierry,
Voliotis Valia,
Grousson Roger,
Schott Michel
Publication year - 2008
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.200879858
Subject(s) - exciton , picosecond , coherence (philosophical gambling strategy) , condensed matter physics , physics , molecular physics , interference (communication) , quantum dot , wave packet , coupling (piping) , quantum , atomic physics , materials science , quantum mechanics , laser , channel (broadcasting) , engineering , electrical engineering , metallurgy
The exciton in single luminescent polydiacetylene (PDA) chains dispersed in their single crystal monomer matrix is studied. As reported these quantum wires have the properties of a perfect quasi‐1D semiconducting system. The macroscopic spatial coherence of a single exciton state on a chain as a function of temperature is investigated using an interference experiment. The interference pattern contrast decreasing with increasing temperature is non zero up to 30 K. Experiments developed in order to observe the regime of formation of the stationary coherent exciton state are described. Within the time resolution of the experiment, it is concluded that the formation of this state is faster than ∼5 picoseconds which confirms the assumption of a transient regime. Finally the first steps of the manipulation of phase locked excitonic wave‐packets on a PDA wire are discussed. The experimental results measured in a weak exciton‐photon coupling regime are compared to simulations obtained through the Bloch optical equations in the framework of a three‐levels model. A direct estimate of the coherence time of the vibronic state photocreated in the present non resonant scheme is derived. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)