AUTHORS:

Yang Y., Zhu K., Wen J., Wang W., Fan X., Dong Y., Luo Y., Shang Y., Pang F., Zhang X., Peng G., Buczynski R., Wang T.

ABSTRACT:

In this study, the gain characteristics of bismuth-doped fiber (BDF) in 1275 nm, 1310 nm, and dual-pump configurations were compared to achieve the broadband amplification. In the 1310 nm pump configuration, the bandwidth of gain >20 dB was 125 nm (1360–1485 nm) and the peak gain at 1430 nm was 37.3 dB. With only 1275 nm pumping, the peak gains occurred at 1360 and 1420 nm, with values of 34.3 and 37.1 dB, respectively. BDF achieved a larger gain bandwidth of 165 nm (1320–1485 nm). In the dual-pump configuration, the bandwidth of gain >20 dB achieved 145 nm in the 1340–1485 nm range, which was narrower than that with 1275 nm pumping. The addition of the 1310 nm pump resulted in a redshift in the bandwidth and weakened the gain intensity of the O-band. This is likely due to the 1310 nm pump wavelength overlaps with the emission wavelength range of the bismuth active centers associated with phosphorus. Therefore, selecting a single-pump configuration is critical for achieving the broadband amplification of bismuth-doped fiber amplifiers.

Optics Communications, 2025, vol. 583, art. 131646, doi: 10.1016/j.optcom.2025.131646