Naslov
Kinetics of holographic recording and spontaneous erasure processes in light- sensitive liquid crystal elastomers

Autori
Gregorc, Marko ; Li, Hui ; Domenici, Valentina ; Ambrožić, Gabriela ; Čopič, Martin ; Drevenšek Olenik, Irena

Izvornik
Materials (1996-1944) 5 (2012), 5; 741-753

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
liquid crystal elastomers; light-sensitive materials; holographic lithography; optical microstructuring; recording kinetics

Sažetak
The optical mechanism for imprinting one- dimensional grating structures into thin films of a light-sensitive monodomain liquid crystal elastomer is investigated by analyzing the time dependence of optical diffraction properties. The recording kinetics shows an irregular oscillatory behavior, which is most expressed at small grating spacings and at temperatures close to the nematic-isotropic phase transition. The oscillations are attributed to the opto-mechanical response of the film, i.e., to contraction of the film during the recording process. At temperatures far below the nematic- isotropic phase transition, the spontaneous erasure kinetics exhibits exponential relaxation with relaxation time following the Arrhenius activation law. However, at temperatures close to the nematic-isotropic phase transition, the erasure process shows an interesting nonmonotonic behavior that we attribute to the non-linear relation between the concentration of the photo-transformed chemical groups and the nematic order parameter.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA