Highly Efficient S-Band Thulium-Doped Fiber Amplifier Employing High-Thulium-Concentration Doping Technique

• Published in: Journal of lightwave technology Vol. 25; no. 8; pp. 2108 - 2114
• Main Authors: Aozasa, S., Masuda, H., Shimizu, M., Yamada, M.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-08-2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amplifiers; Applied sciences; Circuit properties; Doped fiber amplifiers; Doping; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Fibers; Gain; glass; Information, signal and communications theory; Integrated optics. Optical fibers and wave guides; Interference; ions; Laboratories; Multiplexing; Noise; Noise levels; Noise measurement; Optical and optoelectronic circuits; Optical fiber amplifiers; Optical fiber communications; optical fiber devices; Optical fibers; Optical telecommunications; Passive optical networks; Signal and communications theory; Stimulated emission; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; thulium; Transmission and modulation (techniques and equipments); Wavelength division multiplexing; wavelength division multiplexing (WDM); Wavelengths; Performance evaluation; Integrated optics; Noise figure; glass; Conversion rate; Doping; optical fibers; Microwave; Doped materials; Wavelength division multiplexing; Amplifiers; Optical fiber amplifiers; S band; optical fiber devices; thulium; wavelength division multiplexing (WDM); Optical fiber communication; ions; Gain; Optical fiber; Cascade connection; High rate transmission
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2007.899793

In the paper, we describe in detail a highly efficient S-band thulium-doped fiber amplifier (TDFA) employing a high-thulium-concentration doping technique. A TDFA with a dual-pass configuration is superior to a TDFA with a single-pass configuration with regard to power-conversion efficiency, whereas it is inferior with regard to noise figure (NF). We propose a cascaded configuration consisting of a single- and double-pass configuration, which provides high efficiency and a low NF. The configuration generated no interference noise, which can result from multipass interference (MPI) with a double-pass configuration. We achieved gains exceeding 26 dB and NFs of less than 7 dB in the 1480-1510-nm wavelength region (30-nm bandwidth). Furthermore, an 8 times 10-Gb/s transmission experiment also confirmed that there was no MPI-induced excess noise.