Investigation of Er3+-Doped Phosphate Glass for L+ Band Optical Amplification

Xiao Shen,Yan Sun,Lili Hu,Xin Wang,Sheng Chen,Wei Wei

doi:10.1109/jphot.2021.3124132

Abstract

In this work, Er 3+ -doped phosphate glass with good flatness of the emission spectrum of the L+ band was prepared by optimizing the content of BaO. The absorption and emission spectra were measured. Increase of BaO content is conducive to the broadening of the emission spectrum in the L+ band. The dependence of flatness with Raman intensity has been shown by linear fitting. The results show that B31 sample has best flatness of the emission spectrum in the L+ band. It is showed that the largest emission cross-section at 1630 nm is 0.0529 × 10 -20 cm 2 and higher than other Er 3+ -doped phosphate glass. Decay curves of the 4 I 13/2 level were measured and the longest fluorescent lifetime is 10.18 ms and longer than other glass except germinate glass. The broadening of the Er 3+ -doped phosphate glass spectrum of the L+ band has been achieved successfully, which provides a reference for the material of optical amplifiers.

Highlights

Since 1980s, Er3+-doped fibers have been developed as optical amplifiers and beenifound important applications in optical communications[1]
Due to the large ionic radius of Ba2+, the increase of Ba2+ concentration will change the symmetry of the electron cloud around oxygen ions, resulting in an increase of molecular refraction and Refractive index (RI) of glass
Each absorption peak corresponds to the transitions from the ground state 4I15/2 to the various excited states 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2, 4I11/2, and 4I13/2 of the Er3+, respectively

Summary

INTRODUCTION

Since 1980s, Er3+-doped fibers have been developed as optical amplifiers and beenifound important applications in optical communications[1]. Among alkaline-earth ions, Ba2+ in phosphate glass shows an advantage of short stress relaxation time, which is key for synthesis of large-scale bulk glass and optical fibers[9]. Rouse et al analyzed the influence of the radius and field strength of alkali metal ions on the structure of phosphate glass[13]. In order to obtain a multi-component phosphate glass with a flatter spectrum of the L+ band, Er3+-doped phosphate glass with the composition of 8Al2O3-22K2O-xBaO- (69.5–x)P2O5- 0.5Er2O3 was prepared. The influence of substituting BaO for P2O5 on the spectrum and structure of phosphate glass was analyzed systematically. A flatter broadening spectrum of the L+ band of the Er3+-doped phosphate glass has been achieved successfully with a longer lifetime

EXPERIMENT

RESULTS AND ANALYSIS

Raman spectroscopy

B10 B15 B20 B24 B28 B31

Absorption and emission cross-sections

CONCLUSIONS