https://doi.org/10.1007/s100510050900
Electro-optical properties of excitons in polydiacetylene chains
1
ETH Zürich, Department of Materials, and Institute of
Polymers, 8092 Zürich, Switzerland
2
Scuola
Normale Superiore, Piazza dei Cavalieri 7,
56126 Pisa, and Istituto Nazionale di Fisica della Materia, Italy
3
University of Technology and Agriculture, S. Kaliskiego 7,
85796 Bydgoszcz, Poland
Corresponding author: a dressler@ifp.mat.ethz.ch
Received:
5
November
1998
Revised:
23
February
1999
Published online: 15 August 1999
We show how to compute the optical functions (reflectivity, transmission, and absorption) of polydiacetylene chains diluted in their monomer matrix exposed to a uniform electric field in the chain direction, in the excitonic energy region. Adopting a model electron-hole potential, we derived an analytical expression for the effective chain susceptibility, which gives the optical functions. The resulting absorption shows excitonic peaks below the gap and Franz-Keldysh oscillations above the gap. The method has been applied for a 3BCMU polydiacetylene chain, showing a good agreement with experimental spectra.
PACS: 78.66.-w – Optical properties of specific thin films, surfaces, and low-dimensional structures / 71.35.-y – Excitons and related phenomena / 71.36.+c – Polaritons (including photon-phonon and photon-magnon interactions)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999
