High gain optical amplification and lasing performance of the Bi/P co-doped silica fiber in the O-band

In this Letter,the optical amplification characteristics of the home-made Bi/P co-doped silica fiber were systematically explored in the range of 1270-1360 nm.The maximum gain of 24.6 dB was obtained in the single-pass amplification device,and then improved to 38.3 dB in the double-pass amplification device for-30 dBm signal power.In addition,we simulta-neously investigated the laser performance of the fiber with the linear cavity.A slope efficiency of 16.4％at～1313 nm was obtained with a maximum output power of about 133 mW under the input pump power of 869 mW at 1240 nm.As far as we know,it is the first laser reported based on the bismuth-doped fiber in China.