Abstract

We report an experimental investigation on the origin of the large optical non-linearity in azo-dye doped nematic liquid crystals. We show that a very large response is obtained for extremely low input light intensity, of the order of a few tens of W/cm 2 , and that it is mediated by the action of the photo-induced voltage on the specific surface coupling agent, which is an ionic surfactant. By performing circular polarization experiments we show that, during the reorientation, the nematic director follows a three-dimensional trajectory composed by in and out-of-plane motion with respect to the incidence plane of the light. We suggest that the bulk contribution is dominated by the photoisomerization of the azo-dye molecules and we report a new kind of self-sustained gratings.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.