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arXiv · 1812.05536

High-speed PAM4-based Optical SDM Interconnects with Directly Modulated Long-wavelength VCSEL

Joris Van Kerrebrouck·Xiaodan Pang·Oskars Ozolins·Rui Lin·Aleksejs Udalcovs·Lu Zhang·Haolin Li·Silvia Spiga·Markus-Christian Amann·Lin Gan·Ming Tang·Songnian Fu·Richard Schatz·Gunnar Jacobsen·Sergei Popov·Deming Liu·Weijun Tong·Guy Torfs·Johan Bauwelinck·Jiajia Chen·Xin Yin
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Abstract

This paper reports the demonstration of high-speed PAM-4 transmission using a 1.5-{\mu}m single-mode vertical cavity surface emitting laser (SM-VCSEL) over multicore fiber with 7 cores over different distances. We have successfully generated up to 70 Gbaud 4-level pulse amplitude modulation (PAM-4) signals with a VCSEL in optical back-to-back, and transmitted 50 Gbaud PAM-4 signals over both 1-km dispersion-uncompensated and 10-km dispersion-compensated in each core, enabling a total data throughput of 700 Gbps over the 7-core fiber. Moreover, 56 Gbaud PAM-4 over 1-km has also been shown, whereby unfortunately not all cores provide the required 3.8 $\times$ 10 $^{-3}$ bit error rate (BER) for the 7% overhead-hard decision forward error correction (7% OH HDFEC). The limited bandwidth of the VCSEL and the adverse chromatic dispersion of the fiber are suppressed with pre-equalization based on accurate end-to-end channel characterizations. With a digital post-equalization, BER performance below the 7% OH-HDFEC limit is achieved over all cores. The demonstrated results show a great potential to realize high-capacity and compact short-reach optical interconnects for data centers.

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Joris Van Kerrebrouck, Xiaodan Pang, Oskars Ozolins, Rui Lin, Aleksejs Udalcovs, Lu Zhang, Haolin Li, Silvia Spiga, Markus-Christian Amann, Lin Gan, Ming Tang, Songnian Fu, Richard Schatz, Gunnar Jacobsen, Sergei Popov, Deming Liu, Weijun Tong, Guy Torfs, Johan Bauwelinck, Jiajia Chen, Xin Yin. 2018-11-13. High-speed PAM4-based Optical SDM Interconnects with Directly Modulated Long-wavelength VCSEL. https://doi.org/10.1109/jlt.2018.2875538

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