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

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. Index Terms-Optical amplifier, Er 3+ -doped phosphate glass, L+ band, Raman spectrum. I. INTRODUCTIONS INCE 1980s, Er 3+ -doped fibers have been developed as optical amplifiers and been found important applications in optical communications [1]. Quartz-based Er 3+ -doped fiber amplifiers (EDFA) have been performed for many years [2]. However, the development of new generation communication demands for broadband emissions at wavelength longer than 1610 nm (L+ band) furtherly [3]. Besides, EDFA is difficult to achieve a flat and efficient gain spectrum in L+ band due to the characteristics of Er 3+ spectrum in silica glass [4].Instead, among glass hosts, phosphate glass shows many advantages such as mature manufacture technology, high transparency, high doped concentration and large-scale component adjustment [5], [6]. Meanwhile, the spectroscopic properties of Er 3+ in phosphate glass can be widely adjusted by changing the composition [7]. For instance, the emission line width of rare Manuscript

Er‐Activated Hybridized Glass Fiber for Broadband Telecommunication

“…For example, the in-band pump technology has been used in phosphate fibers to compensate the low-emission cross-section of Er 3+ ions in L-band, and the extended amplification in L+ band has been achieved. [19][20][21] The above-mentioned fibers have demonstrated good performance in single-stage optical amplification in L-band. However, their physical and chemical properties are quite different than those of silica materials.…”