Development of a new pump laser for high output power, low power consumption Raman amplifiers by expanding the range of the FRL1441U Series to support the S-band and L-band

Furukawa Electric Co., Ltd. (Head office: 2-6-4 Otemachi, Chiyoda-ku, Tokyo; President: Keiichi Kobayashi) has expanded the product lineup through the development of new applications for the S-band and L-band by extending the normal C-band range of the FRL1441U Series pump laser of high output power, low power consumption for Raman amplifiers. We will start shipping product samples from April 2023 and begin mass production from September 2023.
The development of a pump laser for Raman amplifiers that support the S-band and L-band was conducted and achieved as part of the National Institute of Information and Communications Technology (NICT) commissioned research “Beyond 5G – Development of extended range optical node technology for realizing ultra-high speed, large volume networks” (Key Issue 045).

As data transmission speed increases, the transmission distance decreases due to degradation of the OSNR (Note 1) on the receiving side. In particular, when existing communication systems are used at faster transmission speeds the role of the Raman amplifier, which can amplify optical output power without attenuation of the signal light quality, has become even more important. Also, because the bandwidth of the signal expands as a result of high-speed transmission, it is necessary to extend the bandwidth in order to enable high volume transmission. Thus, Raman amplifiers, which make it possible to amplify the signal light source based on the selection of the pump laser wavelength, offer the most flexibility for optical amplification.
We have contributed to the advancement of optical communications for over 20 years as a leading company in the manufacture of pump lasers, a key component of Raman amplifiers.

Concerning our FRL1441U Series pump laser for Raman amplifiers, in addition to the 700mW C-band pump laser developed last year, the new lineup will be expanded to include products for S-band and L-band applications. With consideration for the energy shift from short wavelength to long wavelength due to the impact of stimulated Raman scattering during optical transmission, we focused on high output power, low power consumption for S-band applications and lower power consumption design for L-band applications. The designs were optimized accordingly, and we developed pump lasers with 700mW output for S-band applications (Fig. 2) and 500mW output, low power consumption (33% lower compared to existing Furukawa Electric products, Fig. 3) for L-band applications. The higher output power and extended bandwidth were realized as a result of the high accuracy fiber coupling technology and optical semiconductor processing technology using InP (Note 2) semiconductor materials developed over the past 25 years, as well as the application of our unique low loss, high efficiency semiconductor laser device structure (Patented). Product samples will start being shipped from April, with mass production to commence from September.
Using this product, it will be possible to reduce the space required by using a single pump laser instead of the previous two pump lasers required for achieving higher output power. At the same time, the reduced power consumption will contribute to reducing the power consumption of the Raman amplifier. Also, with the expanded lineup, it will be possible to supply components for Raman amplifiers that can selectively amplify the signal light source from the S-band through the L-band, thus contributing to the realization of ultra-high speed, high volume transmission networks.

We will exhibit this new product at OFS 2023 scheduled to be held on March 7-9, 2023 in San Diego (OFS Fitel, LLC booth; Booth number 3229).

OFC 2023