Ferroelectric domain boundaries are quasi-two-dimensional functional interfaces with high prospects for nanoelectronic applications. Despite their reduced dimensionality, they can exhibit complex non-Ising polarization configurations and unexpected physical properties. Here, the impact of the three-dimensional (3D) curvature on the polarization profile of nominally uncharged 180° domain walls in LiNbO is studied using second-harmonic generation microscopy and 3D polarimetry analysis.
View Article and Find Full Text PDFOne of the most characterized bioluminescent reactions involves the firefly luciferase that catalyzes the oxidation of the luciferin producing oxyluciferin in its first excited state. While relaxing to the ground state, oxyluciferin emits visible light with an emission maximum that can vary from green to red. Oxyluciferin exists under six different chemical forms resulting from a keto/enol tautomerization and the deprotonation of the phenol or enol moieties.
View Article and Find Full Text PDFA long focal length focusing device is proposed for the process of glass welding by femtosecond laser pulses at high repetition rate and we report on the significant advantages. The study is performed using a 100 mm focusing length F-theta lens. The results are compared to those obtained with a high numerical aperture microscope objective.
View Article and Find Full Text PDFFirefly bioluminescence is a quite efficient process largely used for numerous applications. However, some fundamental photochemical properties of the light emitter are still to be analyzed. Indeed, the light emitter, oxyluciferin, can be in six different forms due to interexchange reactions.
View Article and Find Full Text PDFThe inscription of light-induced self-written waveguides (LISW) with multimode optical fibers cannot be achieved by using coherent light because of the filamentation phenomena coming from the interferences among the different propagating modes. To suppress this filamentation, we have used two distinct strategies, an incoherent light writing technique and an "on the flow" writing process, to demonstrate the buildup of 1.5 mm long multimode LISWs.
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