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Breakthrough: Beyond 300 Gbit/s optical communication speed

Published Jan 21, 2021

Beyond 300 Gbit/s communication speed achieved as a result from collaboration with Finisar.

A collaboration between Finisar and KTH has yielded directly modulated lasers with more than 65 GHz modulation bandwidth [1, 2]. This is the highest modulation bandwidth achieved for monolithic InGaAsP/InP lasers. A side mode was utilized to extend the modulation bandwidth beyond that of conventional semiconductor lasers; a technique that was discovered and pioneered by KTH in the 1990's [3]. Experiments performed at Nokia Bell Labs demonstrates that the lasers can be used for data transmission beyond 300 Gbit/s, using novel multi-level modulation formats. Another benefit is that they are also tolerant to back reflections and can be used without optical isolator, which facilitates their use in optical transceivers in datacenters.

[1] U. Troppenz & Jochen Kreissl, Semiconductor Lasers: Designs break bandwidth record, Nat. Photonics15, 4–5 (2021).

[2] Y. Matsui., R. Schatz, D. Che, et al. Low-chirp isolator-free 65-GHz-bandwidth directly modulated lasers. Nat. Photonics 15, 59–63 (2021).

[3] O. Kjebon, R. Schatz, S. Lourdudoss, S. Nilsson, B. Stalnacke and L. Backbom, "Two-section InGaAsP DBR-lasers at 1.55 /spl mu/m wavelength with 31 GHz direct modulation bandwidth," Conference Proceedings. 1997 International Conference on Indium Phosphide and Related Materials, Cape Cod, MA, USA, 1997, pp. 665-668, doi: 10.1109/ICIPRM.1997.600265.

Page responsible:Max Yan
Belongs to: Photonics
Last changed: Jan 21, 2021