| mots-clés : Microscopie électro-optique – effet électro-optique – optique non linéaire moléculaire – biophotonique – microscope confocal – détection homodyne – mesures de champs électriques – polymères non linéaires quadratiques – asservissement de phase optique |
| autres localisations : http://www.lpqm.ens-cachan.fr/theses/thesetoury.pdf |
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Electro-Optical Microscopy
From Theory to Applications |
| Electro-optical microscopy is a micrometric quantitative mapping technique of electrical fields and of electro-optical tensor components in a medium. The set-up is a confocal microscope included in an interferometer with homodyne detection used to record and measure weak phase shifts due to Pockels effect. The sample must be transparent, quadratically nonlinear and submitted to an intrinsic or externally applied electric field. This doctoral dissertation introduce the concept of electro-optical microscopy. The realization of the microscope is then detailed. The two dimensionnal electro-optical mapping obtained in a polymer film is discussed. Finally, we demonstrate for the first time a Pockels effect induced phase shift in a doped phospholipidic membrane. Applications perpectives to biological transmembranar potentials are presented. In conclusion, technological difficulties of this application are detailled and solutions are suggested. |
| mots-clés en anglais : Electro-optical microscopy – electro-optical effect – molecular nonlinear optics – biophotonics – confocal microscopy – homodyne interferometry – electric field measurement – poled polymers – optical phase lock-in |
