Er 3+ /Ce 3+ Co-doped Phosphosilicate Fiber for Extend the L-band Amplification

Withthe advent of the 5G era, the demand for data communication is increasing explosively. Extending the L-band gain bandwidth is considered to be the most direct and effective approach to increasing communication capacity. However, the signal excited state absorption (SESA) prevents the L-band gain from extending to longer wavelength. In this report, Er3+ and Ce3+ are introduced into the phosphosilicate fiber to regulate the SESA. The results show that the addition of Ce3+ into the phosphosilicate fiber can weaken the effect of SESA and extend the L-band gain bandwidth. The SESA of the Er3+/Ce3+ co-doped phosphosilicate fiber do not begin until 1620 nm, which is shifted and suppressed efficiently. The longest wavelength of the Er3+/Ce3+ co-doped phosphosilicate fiber is extended to 1623 nm. This result provides an effective approach to realizing the extended L-band amplification.