Twisted polydiacetylene quantum wire: Influence of conformation on excitons in polymeric quasi-one-dimensional systems

Antoine Al Choueiry (1) , Thierry Barisien (1) , J. Holcman (1) , Laurent Legrand (1) , Michel Schott (1) , Gerhard Weiser (2) , Mirela Balog (3) , Jérôme Deschamps (3) , Sylvain G. Dutremez (3) , Jean-Sébastien Filhol (3)

1 INSP - Institut des Nanosciences de Paris
2 Fachbereich Physik [Marburg]
3 ICGM ICMMM - Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier

Highly luminescent isolated polydiacetylene (PDA) chains in a new diacetylene crystal are studied. The diacetylene crystal structure and theoretical calculations suggest that the chains are not planar and more strongly twisted than any known PDA. Yet the chains behave as quasiperfect quantum wires, showing that this behavior is generic among PDA, provided crystal order is high enough. The exciton energy, E0, is higher than in any other well-ordered PDA providing a relationship between E0 and twist angle. On the other hand, the exciton binding energy and Bohr radius are significantly affected as demonstrated in electroabsorption experiments (and developed in a companion paper).

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Antoine Al Choueiry, Thierry Barisien, J. Holcman, Laurent Legrand, Michel Schott, et al.. Twisted polydiacetylene quantum wire: Influence of conformation on excitons in polymeric quasi-one-dimensional systems. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2010, 81 (12), pp.125208-1-125208-11. ⟨10.1103/PhysRevB.81.125208⟩. ⟨hal-00566209⟩