Silica Micro-Rod Resonator-Based Kerr Frequency Comb for High-Speed Short-Reach Optical Interconnects
Optics Express 2023
Rihards Mūrnieks, Toms Salgals, Jānis Alnis, Armands Ostrovskis, Oskars Ozoliņš, Inga Brice, Arvīds Sedulis, Kristians Draguns, Ilya Lyashuk, Roberts Berķis, Aleksejs Udaļcovs, Toby Bi, Xiaodan Pang, Jurģis Poriņš, Sandis Spolītis, Pascal Del’Haye, Vjačeslavs Bobrovs

Conventional data center interconnects rely on power-hungry arrays of discrete wavelength laser sources. However, growing bandwidth demand severely challenges ensuring the power and spectral efficiency toward which data center interconnects tend to strive. Kerr frequency combs based on silica microresonators can replace multiple laser arrays, easing the pressure on data center interconnect infrastructure. Therefore, we experimentally demonstrate a bit rate of up to 100 Gbps/λ employing 4-level pulse amplitude modulated signal transmission over a 2 km long short-reach optical interconnect that can be considered a record using any Kerr frequency comb light source, specifically based on a silica micro-rod. In addition, data transmission using the non-return to zero on-off keying modulation format is demonstrated to achieve 60 Gbps/λ. The silica micro-rod resonator-based Kerr frequency comb light source generates an optical frequency comb in the optical C-band with 90 GHz spacing between optical carriers. Data transmission is supported by frequency domain pre-equalization techniques to compensate amplitude–frequency distortions and limited bandwidths of electrical system components. Additionally, achievable results are enhanced with offline digital signal processing, implementing post-equalization using feed-forward and feedback taps.

optical frequency comb (OFC), whispering gallery mode resonator (WGMR), wavelength-division multiplexing (WDM), dat center interconnects (DCI)

Mūrnieks, R., Salgals, T., Alnis, J., Ostrovskis, A., Ozoliņš, O., Brice, I., Sedulis, A., Draguns, K., Lyashuk, I., Berķis, R., Udaļcovs, A., Bi, T., Pang, X., Poriņš, J., Spolītis, S., Del’Haye, P., Bobrovs, V. Silica Micro-Rod Resonator-Based Kerr Frequency Comb for High-Speed Short-Reach Optical Interconnects. Optics Express, 2023, Vol. 31, No. 12, pp.20306-20320. ISSN 1094-4087. Available from: doi:10.1364/OE.488436

Publication language
English (en)
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