Laser Direct Writing of Silver Clusters‐Based Subwavelength Periodic Structures Embedded in Mid‐Infrared Gallo‐Germanate Glass

Abstract

Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Photochemistry of Bismuth- and Silver-Containing Glasses under Femtosecond Laser Irradiation: Energy Transfers and 3D-localized Background-Free Near-Infrared Fluorescence Emission

“…However, Ag m x+ and Bi + fluorescence double-tracks are sharper and further away from the center of the voxel of the laser/matter interaction. Thus, such double-track modifications could be due to the occurrence of the photodissociation and photodiffusion effect for both silver clusters and Bi 2+ , similar to that observed in the glasses containing only silver. , The lower size and high mobility of silver species (Ag 0 and Ag + ) compared to bismuth ions could explain the higher internal distance of Ag m x+ fluorescence. We can also suggest the higher photodestruction of created silver clusters in the center of the voxel of the laser/matter interaction compared to Bi 2+ .…”

“…Moreover, without the presence of silver ions, only single-track laser modification is observed at the considered irradiation condition, being associated with a much weaker Bi 2+ fluorescence emission intensity. Under fs laser irradiation, Ag + ions can get ionized, thus behaving as a reservoir to create free electrons. , Thus, without the presence of silver ions, laser irradiation leads to a much weaker generation of free electrons, thus leading to a much weaker probability of reducing Bi 3+ ions into Bi 2+ . The fact that the Bi 2+ emission shows either a bright double-track feature or a less intense single-track when considering glasses with or without silver, respectively, results from the cumulative multipulse management of the silver reservoir. , In the presence of silver, the dynamics of Bi 2+ creation is dominated by the creation dynamics of free electrons, which is directly linked to the diffusion of silver species from the center of the laser irradiation voxel to its edges, leading to the bright double-track feature.…”

“…Under fs laser irradiation, Ag + ions can get ionized, thus behaving as a reservoir to create free electrons. 8,10 Thus, without the presence of silver ions, laser irradiation leads to a much weaker generation of free electrons, thus leading to a much weaker probability of reducing Bi 3+ ions into Bi 2+ . The fact that the Bi 2+ emission shows either a bright double-track feature or a less intense single-track when considering glasses with or without silver, respectively, results from the cumulative multipulse management of the silver reservoir.…”

“…Miniaturization of 3D multiscale architecture is indeed of interest for the development of a Photonic Integrated Circuit (PIC) and applications in several areas such as sensing, data communication, biomedicine, and optical storage. − The unique advantage of Femtosecond (fs) Direct Laser Writing (DLW) due to its flexibility, ultrafast micro processing, and high precision allows highly localized modification of photosensitive transparent dielectric, resulting in a low-scale photonic component (PIC). Recently, we have demonstrated the capability to structure the local fluorescence property of silver-containing glasses using fs DLW, allowing the local creation of an elementary brick with inner features down the diffraction limit (<100 nm). − This structuration relies on the creation of highly fluorescent silver clusters (Ag m x+ ) formed by local aggregation of silver atoms (Ag 0 ) and silver ions (Ag + ) thanks to fs laser-activated redox reactivity and migration of silver ions in the glass matrix . For UV to visible excitation, such a laser-induced silver-cluster-containing structure exhibits a broad emission band in the visible range.…”

Toward low-loss mid-infrared Ga2O3–BaO–GeO2 optical fibers

“…Since the discovery of the barium-gallium-germanium (BGG) glasses in the 1990s 8 , considerable efforts have been deployed to further enhance the glass properties 9 – 13 , draw them into fibers 14 – 16 and also functionalize them 17 – 19 . In the meantime, gallium-rich, namely gallate, BGG glasses (GaO 3/2 /GeO 2 ratio in mol% larger than 1) have attracted significant attention, since their thermal, optical and mechanical properties are even superior to those of germanate-based BGG compositions (GaO 3/2 /GeO 2 ratio in mol% smaller than 1).…”