Er3+‐Tm3+ Co‐Doped Hybridized Gadolinium Aluminosilicate Glass Fiber for Broadband Optical Amplification

Abstract Optical fiber communication has greatly promoted the development of the information age, while the emergence of 5G networks, cloud computing, and artificial intelligence have put forward high challenges to the capacity of current optical fiber communication systems. At present, increasing the bandwidth of erbium‐doped fiber amplifiers (EDFA) is the most effective way to increase the communication capacity. In this paper, a hybridization strategy is proposed for simultaneous achieving strong and flat optical response and demonstrate the success in construction of Er 3+ ‐Tm 3+ co‐doped gadolinium aluminosilicate glass fiber for L‐band optical amplification. Gd 3+ ions are introduced to enhance the radiative transition by improving the dispersibility of Er 3+ . Tm 3+ ions are co‐introduced to facilitate energy transfer between Er 3+ and Tm 3+ for achieving flat emission in the L‐band. The hybridized active fiber which can be effectively fused with quartz fiber is fabricated by melt‐in‐tube (MIT) approach. A fiber amplifier is construed and it enables to achieve a flat on‐off gain (<±0.76 dB) across the L‐band spectrum. These results indicate that Er 3+ ‐Tm 3+ co‐doped hybridized gadolinium aluminosilicate glass fiber is a promising gain material for fiber amplifiers and demonstrate that the hybridization approach provides a new strategy for the development of novel active fiber device.