Multi-Band Programmable Gain Raman Amplifier

• Published in: Journal of lightwave technology Vol. 39; no. 2; pp. 429 - 438
• Main Authors: de Moura, Uiara Celine, Iqbal, Md Asif, Kamalian, Morteza, Krzczanowicz, Lukasz, Da Ros, Francesco, Brusin, Ann Margareth Rosa, Carena, Andrea, Forysiak, Wladek, Turitsyn, Sergei, Zibar, Darko
• Format: Journal Article
• Language: English
• Published: New York IEEE 15.01.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amplification; Bandwidth; Bandwidths; C band; Communications systems; Equalization; Gain; Light amplifiers; Machine learning; multi–band systems; neural networks; Nonlinear optics; optical amplifiers; Optical attenuators; Optical communication; optical communications; Optical frequency; Optical pumping; Pump lasers; Raman spectra; Spectrum allocation; Stimulated emission; Systems design
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2020.3033768

Optical communication systems, operating in C-band, are reaching their theoretically achievable capacity limits. An attractive and economically viable solution to satisfy the future data rate demands is to employ the transmission across the full low-loss spectrum encompassing O, E, S, C, and L band of the single mode fibers (SMF). Utilizing all five bands offers a bandwidth of up to <inline-formula><tex-math notation="LaTeX">\sim</tex-math></inline-formula>53.5 THz (365 nm) with loss below 0.4 dB/km. A key component in realizing multi-band optical communication systems is the optical amplifier. Apart from having an ultra-wide gain profile, the ability of providing arbitrary gain profiles, in a controlled way, will become an essential feature. The latter will allow for signal power spectrum shaping which has a broad range of applications such as the maximization of the achievable information rate × distance product, the elimination of static and lossy gain flattening filters (GFF) enabling a power efficient system design, and the gain equalization of optical frequency combs. In this paper, we experimentally demonstrate a multi-band (S+C+L) programmable gain optical amplifier using only Raman effects and machine learning. The amplifier achieves <inline-formula><tex-math notation="LaTeX">></tex-math></inline-formula>1000 programmable gain profiles within the range 3.5 to 30 dB, in an ultra-fast way and a very low maximum error of <inline-formula><tex-math notation="LaTeX">1.6 \cdot 10^{-2}</tex-math></inline-formula> dB/THz over an ultra-wide bandwidth of 17.6-THz (140.7-nm).