Space-selective growth of frequency-conversion crystals in glasses with ultrashort infrared laser pulses

Abstract

We report on space-selective growth of a second-harmonic-generation beta-BaB(2)O(4) (BBO) crystal inside a BaO-Al(2)O(3)-B(2)O(3) glass sample at the focal point of an 800-nm femtosecond laser beam. A spherical heated region was formed during the focused laser irradiation through observation with an optical microscope. We moved the heated region by changing the position of the focal point of the laser beam relative to the glass sample. We grew BBO crystal continuously in the glass sample by adjusting the moving speed of the heated zone. Our results demonstrate that functional crystals can be formed three dimensionally in glasses by use of a nonresonant ultrashort pulsed laser.

Direct laser writing of efficient effective second order nonlinear optical properties in a tailored silver-doped phosphate glass

“…Nonlinear optical contrast can also appear from third-order nonlinear response enhancement due to density contrast, as proposed for perennial high density data storage [3,4]. DLW also showed second-order nonlinear optical properties, even in a glassy environment, either due to the localized crystallization of non-centrosymmetric nanocrystalittes [5] or to the production of a buried static space charge separation at the root of the electric field induced second harmonic generation (EFISHG) [6].Laser-induced optical poling, leading to the EFISHG effect, is a very promising approach. Indeed, it generates very limited index changes, no phase transition and no interface, which prevents any potential high refractive index contrast and the associated drawback of light diffusion as generally the case for nano-crystallisation in bulk glassy matrices [5].…”

“…Nonlinear optical contrast can also appear from third-order nonlinear response enhancement due to density contrast, as proposed for perennial high density data storage [3,4]. DLW also showed second-order nonlinear optical properties, even in a glassy environment, either due to the localized crystallization of non-centrosymmetric nanocrystalittes [5] or to the production of a buried static space charge separation at the root of the electric field induced second harmonic generation (EFISHG) [6].…”

“…DLW also showed second-order nonlinear optical properties, even in a glassy environment, either due to the localized crystallization of non-centrosymmetric nanocrystalittes [5] or to the production of a buried static space charge separation at the root of the electric field induced second harmonic generation (EFISHG) [6].…”

“…Indeed, it generates very limited index changes, no phase transition and no interface, which prevents any potential high refractive index contrast and the associated drawback of light diffusion as generally the case for nano-crystallisation in bulk glassy matrices [5]. Laser-induced optical poling is thus a powerful approach for three-dimension high density data encoding, with multiple layers in the depth of the photosensitive material, which cannot be performed under thermally-assisted electric poling where the very strong permanent static electric field, leading to a few pm/V effective EFISHG amplitude, is limited to surface structuring with depths typically limited to 10 μm [7].…”

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

“…Thus, for the laserinduced linear properties, DLW can lead to plasmonic enhancement from nanoparticles [2], fluorescence from metallic clusters [3] or oxidation degree modifications of rare earth ions [4]. For the nonlinear properties, second-harmonic generation (either from locally buried electric field [5] or from locally laser-induced micro-crystallization [6]) or third-harmonic generation [7] can be obtained.…”