Numerical and limited experimental study of 1150 nm signal amplification based on bismuth-doped fiber using 980 nm pumping

In this paper, a bismuth-doped fiber amplifier based on bismuth-aluminum-fluorine co-doping fiber is numerically simulated. The amplifier is a three-energy level structure with pump and signal wavelengths of 980 nm and 1150 nm. The different pump powers, signal powers, doping concentrations, and pump structures are adopted to investigate the effects on the gain and noise figure of the amplifier. Moreover, limited experimental results are utilized here to verify the applicability of the three-energy amplification system model to the bismuth-doped fiber amplifier (BDFA). The results show that the signal received a gain of more than 25 dB at a pump power of 500 mW for a signal input power of − 10 dBm under the forward pumping scheme, while the noise figure is around 3.2 dB. The forward pumping under the same conditions does not show a significant disadvantage compared to the bidirectional pumping, and the gain is only 1.6 % lower than the latter. In addition, the experimental results of single-mode BDFA still fit the three-energy system amplifier simulation model to some extent. The analysis supplies a positive reference for the development of amplifiers near 1150 nm, which has potential applications in medical or astronomical fields.