Generation and power amplification of 1.4-μm ultra-broadband noise-like pulses using a bismuth-doped germanosilicate fiber laser and amplifier
Year: 2026
Type: article
Abstract: The 1.4–1.5 μm spectral region is attractive for water‑absorption‑related photonic applications and E- and S-band optical communication systems, but suitable silica-compatible gain media remain limited. We developed a single-mode, low-germanium bismuth-doped germanosilicate fiber (BGSF) and used this common fiber platform as the gain medium for both a laser and an amplifier. To our knowledge, this all-fiber laser system provides the first demonstration of ultra-broadband noise-like pulse (NLP) generation and efficient power scaling at 1.4 μm. With a seed power of 13.59 mW, the amplifier delivered an average output power of 103 mW and a pulse energy of 26.30 nJ, corresponding to a 7.6-fold power increase and a slope efficiency of approximately 79 %. The amplified pulse train exhibited a radio-frequency signal-to-noise ratio of 59.72 dB. Meanwhile, the typical dual-scale autocorrelation signature of NLPs was well preserved, whereas the coherent spike width broadened from 284 fs to 553 fs. The amplifier also broadened the 3-dB spectral bandwidth from 9.18 to 13.81 nm and the 10-dB bandwidth from 14.38 to 68.69 nm. At the maximum amplifier pump power of 178 mW, the measured amplified spectral coverage extended from 1400 nm to beyond 1650 nm (20-dB bandwidth > 197.74 nm). These results show that the low-germanium BGSF-based all-fiber laser and amplifier can support ultra-broadband NLP generation and efficient power amplification at 1.4 µm.
Source: Optics & Laser Technology
Institutions: Soochow University, Collaborative Innovation Center of Suzhou Nano Science and Technology, Key Lab of Modern Optical Technologies of Education Ministry of China, Fiber Optics Research Center, Prokhorov General Physics Institute, Institute of Chemistry of High-Purity Substances them. G.G.Devyatyh
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,230
OpenAlex ID: W7222798698