The authors would like to thank Dr. Marco Salerno, Dr. Francesco Rizzi, Dr. Monica Distaso, and Dr. Claudio Canale of the Italian Institute of Technology for their contribution to the experimental work.
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Full Paper
Reversible Diffraction Efficiency of Photochromic Polymer Gratings Related to Photoinduced Dimensional Changes†
Article first published online: 21 MAY 2008
DOI: 10.1002/adfm.200701255
Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Additional Information
How to Cite
Fragouli, D., Persano, L., Paladini, G., Pisignano, D., Carzino, R., Pignatelli, F., Cingolani, R. and Athanassiou, A. (2008), Reversible Diffraction Efficiency of Photochromic Polymer Gratings Related to Photoinduced Dimensional Changes. Advanced Functional Materials, 18: 1617–1623. doi: 10.1002/adfm.200701255
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Publication History
- Issue published online: 12 JUN 2008
- Article first published online: 21 MAY 2008
- Manuscript Revised: 23 JAN 2008
- Manuscript Received: 30 OCT 2007
- Abstract
- References
- Cited By
Keywords:
- Laser irradiation;
- Optical switches;
- Photochromic materials;
- Soft lithography;
- Spiropyrans
Graphical Abstract
Relative diffraction efficiency changes of an imprinted grating, which consists of polyethylmethacrylate-co-methylacrylate polymer doped with 10 wt% of spiropyran, following cycles of UV and visible laser light irradiation are measured (see figure). After UV irradiation the stripes reduce in size, resulting in an increase of the diffraction efficiency. Consequent irradiation with visible light causes the recovery of the stripes' width and thus of the diffraction efficiency, which returns close to the initial values.
Abstract
In this Full Paper, the possibility of reversibly changing the diffraction efficiency of gratings, fabricated by soft molding lithography on polymer films, containing photochromic molecules, is demonstrated. In particular, alternating UV and visible laser irradiation of the gratings causes the doped photochromic molecules to undergo transformations, which induce reversible dimensional changes to the samples. As a result, reversible changes are monitored in the intensity of the beams of a diode laser, transmitted and diffracted from the gratings. These changes affect the diffraction efficiency, which is increased upon irradiation with UV and decreased after irradiation with visible laser light. Such gratings are promising candidates for the fabrication of modern optical components such as optical switching devices.