Conductivity of oriented bis-azo polymer films.
The conductivity properties of electro-optic, photoaddressable, dense bis-azo chromophore polymer films are investigated by using samples corona poled at various temperatures. A dielectric spectrometer is applied to measure the frequency dependence of the conductivity at different temperatures before and after heating the material to above the glass transition temperature. The results show that the orientation of the chromophores changes the charge-carrier mobility. Ionic conductivity dominates in a more disordered configuration of the material, while the competing process of hole hopping takes over as a transition to a liquid-crystalline phase occurs when the material is heated to much higher than the glass transition temperature. Such microcrystallization strongly enhances the conductivity.
Apitz
Dirk
D
Optics and Plasma Research Department, Risø National Laboratory, 4000 Roskilde (Denmark). dirk.apitz@risoe.dk
Bertram
Ralph Peter
RP
Benter
Nils
N
Sommer-Larsen
Peter
P
Johansen
Per Michael
PM
Buse
Karsten
K