Low-pump-power, short-fiber copropagating dual-pumped (800 and 1050nm) thulium-doped fiber amplifier (original) (raw)

Broadband silica-based thulium doped fiber amplifier employing multi-wavelength pumping

Optics express, 2016

A multi-wavelength pumped thulium doped fiber amplifier is investigated to extend the spectral gain coverage of the amplifier in the 1.7-1.9μm wavelength range. Through the use of a combination of 791 nm, 1240 nm, and 1560 nm laser diode pumping, the amplifier gain can be improved significantly and overall gain bandwidth enhancement of ~47% as compared to single-wavelength pumping achieved. A nominal gain of 15 dB is achieved over a bandwidth of more than 250 nm spanning from 1700 to 1950 nm with a maximum gain of 29 dB and a noise figure of less than 5 dB.

100 W, Tunable In-band Pumped Thulium Fiber Amplifier

We detail the design and performance of a high efficiency in-band pumped thulium fiber amplifier operating at the 100 W level. Using a novel pumping architecture based on three incoherently combined thulium fiber oscillators at 1904 nm and a seed laser tunable from 1970-1990 nm, efficient amplification is demonstrated in a high dopant concentration 25/65/250 μm thulium fiber. Here we use the 65 μm pedestal surrounding the core as a pump cladding to increase the cladding to core overlap and improve the overall pump absorption. Up to 89% slope efficiency is obtained with ~100 W output power at 1990 nm. These results indicate that in-band pumping is a viable route to circumvent the thermal limitations associated with 793 nm diode pumping and provide a pathway for development of multi-kW laser sources in the 2 μm spectral window.

Thulium Doped Fiber Amplifier (TDFA) for S-band WDM Systems

Open Journal of Applied Sciences

A comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier is evaluated. The pump power and thulium-doped fiber (TDF) length for single-pass Thulium-Doped Fiber Amplifiers (TDFA) are theoretically optimized to achieve the optimum Gain and Noise Figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result.