Erbium and Al2O3 nanocrystals-doped silica optical fibers

Abstract

Abstract. Fibre lasers and inherently rare-earth-doped optical fibers nowadays pass through a new period of their progress aiming at high efficiency of systems and their high power. In this paper, we deal with the preparation of silica fibers doped with erbium and Al2O3 nanocrystals and the characterization of their optical properties. The fibers were prepared by the extended Modified Chemical Vapor Deposition (MCVD) method from starting chlorides or oxide nanopowders. Conventional as well as modified approaches led to a nanocrystalline mullite phase formation in the fiber cores in which erbium is dissolved. The proposed modified approach based on starting nanopowders led to improved geometry of preforms and fibers and consequently to the improvement of their background attenuation. Such nanocrystal -doped fibers can be used for ASE sources. Further improvement of fiber optical properties can be expected.

Synthesis and characterization of rare earth‐doped silica nanoparticles for optimizing vapor phase doping technique

“…Moreover, all the aluminosilicate phases convert to mullite and cristobalite in the temperature range of 1335‐1625°C . So, in this study possible crystal phases that can be present are α‐Al 2 O 3 , cristobalite, and mullite . But from the diffraction peaks, no crystal phases of pure compounds (SiO 2 or Al 2 O 3 ) could be identified and it indicates only mullite crystals are present.…”

“…33 So, in this study possible crystal phases that can be present are a-Al 2 O 3 , cristobalite, and mullite. 15,25,34 But from the diffraction peaks, no crystal phases of pure compounds (SiO 2 or Al 2 O 3 ) could be identified and it indicates only mullite crystals are present. It should be noted further, according to the SiO 2 -Al 2 O 3 phase diagram, eutectic point of the system is 1595°C along with the composition of 5 mol% Al 2 O 3 and~95 mol% SiO 2.…”

“…A number of researcher groups are working in recent times, toward the minimization of this problem and improvement of the quality of SD‐made fibers by introducing dopant nanoparticles synthesized via different routes . It has been reported that the use of Al 2 O 3 nanoparticles diminishes “star‐like” defect formation as well as improves RE homogeneity in the host glass matrix . But to the best of the authors’ knowledge, no such study has been taken up till date to correlate fabrication conditions of VPD process with the characteristics of RE‐doped soot particles which will consequently result in uniform RE distribution and thus, improve fiber performance.…”

“…[11][12][13] It has been reported that the use of Al 2 O 3 nanoparticles diminishes "star-like" defect formation as well as improves RE homogeneity in the host glass matrix. 14,15 But to the best of the authors' knowledge, no such study has been taken up till date to correlate fabrication conditions of VPD process with the characteristics of RE-doped soot particles which will consequently result in uniform RE distribution and thus, improve fiber performance. Most of the prior arts focused on the particle size distribution of pure components (viz.…”

Thulium-doped fibre broadband source for spectral region near 2 micrometers

“…TDFs with enhanced 3 F 4 life− times of 400-700 μs have been reported in modified silica glasses [16]. A promising way to enhance the fluorescence lifetime is to modify locally thulium environment by the ceramic nanoparticle doping and MCVD methods [41][42][43][44].…”