Broadband infrared light-emitting patterns in optical glass by laser-induced nanostructuring of NiO-doped alkali-gallium germanosilicates

Abstract

In this Letter, we show functionalization of NiO-doped 7.5Li(2)O·2.5Na(2)O·20Ga(2)O(3)·35SiO(2)·35GeO(2) glass by space-selective nanocrystallization via exposure to the focused beam of a pulsed copper vapor laser (510.6 and 578.2 nm) at temperature close to the glass transition point (570°C). Irradiated areas drastically change their color, caused by electronic transitions of Ni(2+) dopant ions, without any alteration of the optical quality. Importantly, irradiated regions acquire broadband infrared luminescence (centered at about 1400 nm and possessing 400 nm effective bandwidth) typical of Ni(2+) ions in crystalline environment, and by positive change of refractive index (more than 10(-3)). Spectroscopic and diffractometric data of the irradiated regions indeed resemble those previously observed in thermally nanocrystallized glass, with Ni(2+) ions embedded in γ-Ga(2)O(3) nanocrystals. The results demonstrate the possibility of laser writing nanocrystallized multifunction patterns in germanosilicate glasses for the fabrication of active integrated devices.

Light-emitting Ga-oxide nanocrystals in glass: a new paradigm for low-cost and robust UV-to-visible solar-blind converters and UV emitters

“…Particularly, no data are available on the intrinsic properties of g-Ga 2 O 3 NCs in glass, since the only studies on embedded variants were essentially aimed at obtaining convenient hosts for IR-emitting ions, such as Ni 2+ and Cr 4+ . 15,17,34 As a result, the data in Fig. 2 constitute the rst quantitative insight into the absorption edge of g-Ga 2 O 3 as a nanophase in a solid matrix.…”

“…[15][16][17] At present, however, data on light emission properties of nanosized Ga oxides are only available for nanopowders and nanowires, or NCs in colloidal solutions. 14,[18][19][20][21][22][23][24][25] A large fraction of those results regard the b-Ga 2 O 3 phase, 4,6,7,[10][11][12][13][14]22 whereas only a few studies concern the metastable polymorph g-Ga 2 O 3 .…”

Diffusion-driven and size-dependent phase changes of gallium oxide nanocrystals in a glassy host

“…3 and 4 point out the crucial role of the interactions between the nanophase and the matrix in the thermal evolution of the embedded NCs. In fact, the registered changes do not correspond to any feature encountered in the transformation paths of g-Ga 2 O 3 and LiGa 5 …”

“…2 Recent results regarding Ga containing oxide glasses suggest that optical properties -such as UV transmittance and UV excited light emission -can be conveniently modified by crystallization of Ga-oxide nanoparticles incorporated in the glass matrix. [3][4][5] These results enable the use of nanocrystal (NC) growth -and NC phase changes inside a solid host -as a tool for functionalizing glass-based materials for information technology. The idea of achieving unprecedented data-storage capability and stability by inducing local modifications of structural and optical functions in glass -specifically by means of focused laser exposure -has recently been envisaged and preliminarily demonstrated in a prototypal system of silica glass.…”

Photocatalytic activity in monodisperse In2O3 nanocrystals incorporated into transparent silica glassy matrix

“…The structure arrangement of nanocrystal-in-glass, for example, not only combines two functional components in one material, but also the covalent link enables us to manipulate the glass structure to change its properties. To the best of our knowledge, some reports have described that incorporating nanocrystalline precipitates within glassy matrices can effectively improve their properties [10][11][12][13][14][15][16][17][18]. Thus selecting a suitable nanocrystal-in-glass system and developing an effective synthetic process for incorporating NCs into glassy matrix becomes very important in the field of materials science.…”