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Ordering of azobenzenes by two-photon isomerization
Hidekazu Ishitobi1, Zouheir Sekkat, Satoshi Kawata
1Nanophotonics Laboratory, RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. ishitobi@riken.jp
The Journal of Chemical Physics
|November 10, 2006
Summary
Two-photon absorption enables light-induced molecular orientation in polymer films containing azobenzenes. This process achieves orientation comparable to traditional one-photon absorption methods.
Area of Science:
- Polymer Science
- Photochemistry
- Materials Science
Background:
- Azobenzene-containing polymers are known for their photoresponsive properties.
- Light-induced molecular orientation is crucial for advanced optical and electronic materials.
Purpose of the Study:
- To investigate light-induced molecular orientation using two-photon absorption in azobenzene polymer films.
- To compare the effectiveness of two-photon absorption with one-photon absorption for inducing molecular orientation.
Main Methods:
- Fabrication of polymer films containing azobenzene molecules.
- Irradiation of films using one-photon and two-photon absorption techniques.
- Analysis of molecular orientation dynamics and degree.
Main Results:
- The dynamics of isomerization and orientation are similar for both one-photon and two-photon absorption.
- Two-photon absorption successfully induces molecular orientation in azobenzene polymer films.
- The degree of orientation achieved by two-photon absorption is comparable to that of single-photon isomerization.
Conclusions:
- Two-photon absorption is an effective method for achieving molecular orientation in azobenzene polymers.
- This finding aligns with theoretical predictions for two-photon isomeric orientation.
- The comparable orientation efficiency suggests potential for advanced applications using two-photon processing.
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