Multi-band programmable gain Raman amplifier

TL;DR

This paper presents an experimental demonstration of a multi-band (S+C+L) programmable gain Raman amplifier that uses machine learning to achieve rapid, precise, and wide-range gain profile control over an ultra-broad bandwidth, advancing optical communication technology.

Contribution

The paper introduces a novel multi-band Raman amplifier with machine learning-based programmable gain control, enabling ultra-fast, accurate, and wide-range gain shaping for optical communications.

Findings

Achieves over 1000 programmable gain profiles from 3.5 to 30 dB.

Operates over an ultra-wide bandwidth of 17.6 THz (140.7 nm).

Maintains a maximum error of 1.6e-2 dB/THz in gain profile accuracy.

Abstract

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 $\sim$53.5THz (365nm) with loss below 0.4dB/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 X 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 >1000 programmable gain profiles within the range from 3.5 to 30 dB, in an ultra-fast way and a very low maximum error of 1.6e-2 dB/THz over an ultra-wide bandwidth of 17.6-THz (140.7-nm).