Fabrication of Alumina-Doped Optical Fiber Preforms by an MCVD-Metal Chelate Doping Method

K A Mat Sharif,H A Abdul-Rashid,N Y M Omar,M I Zulkifli,S Z Muhamad Yassin

doi:10.3390/app10207231

K A Mat Sharif, H A Abdul-Rashid + Show 3 more

Open Access

https://doi.org/10.3390/app10207231

Copy DOI

Journal: Applied Sciences	Publication Date: Oct 16, 2020
Citations: 5	License type: CC BY 4.0

Affiliation: Multimedia University

Abstract

This paper reports on the fabrication of alumina-doped preforms using a modified chemical vapor deposition (MCVD)-vapor phase chelate delivery system with Al(acac)3 as the precursor. The objectives of this work are to study the deposition process, the efficiency of the fabrication process, and the quality of the fabricated fiber preforms. Two parameters are studied, the Al(acac)3 sublimator temperature (TAl °C) and the deposition direction (i.e., downstream and upstream). Other parameters such as the oxygen flow and deposition temperature are fixed. The results show that high uniformity of the refractive index difference (%RSD < 2%) and core size (%RSD < 2.4%) was obtained along the preform length using downstream deposition, while for the combined upstream and downstream deposition, the uniformity deteriorated. The process efficiency was found to be about 21% for TAl °C of 185 °C and downstream deposition. From the EDX elemental analysis, the refractive index was found to increase by 0.0025 per mole percent of alumina.

Highlights

Alumina (Al2 O3 ) is an interesting dopant material for silica optical fiber technology
The fabrication techniques used were outside vapor deposition (OVD), vertical axial deposition (VAD), and modified chemical vapor deposition (MCVD)
The most common technique for doping alumina is conventional MCVD with solution doping (e.g., [8]). This technique has been very successful in the fabrication of fiber amplifiers such as erbium-doped fiber (EDF)

Summary

Introduction

Alumina (Al2 O3 ) is an interesting dopant material for silica optical fiber technology. It does function as a refractive index raiser and helps dissolve other co-dopants such as rare-earth elements in the silica matrix. Alumina is very essential to the fabrication of rare-earth-doped fiber amplifiers and high-power fiber lasers. The most common technique for doping alumina is conventional MCVD with solution doping (non-vapor phase) (e.g., [8]). This technique has been very successful in the fabrication of fiber amplifiers such as erbium-doped fiber (EDF)

Objectives

Methods

Discussion

Conclusion