Raman and fluorescence correlative microscopy in polarized light to probe local femtosecond laser-induced amorphization of the doped monoclinic crystal LYB:Eu

We report on Raman and fluorescence microscopy in polarized light in the oriented Eu3+-doped LYB monoclinic crystal after femtosecond laser irradiation. Differential spectra denote large bands typically centered on the pristine glass Raman and fluorescence lines, proving the crystal structure alteration and the significant existence of a laser-induced glassy environment of the Eu3+ ions inside the laser-induced modified zone. Such approach should be annotated for future control of direct laser writing onto biaxial crystals such as LYB:Eu. This is of tremendous interest to probe in situ local modifications, in order to develop new laser-induced optical properties in materials for further photonics applications.