100Gb/s PAM4 oxide VCSEL development progress at Broadcom

Recent Advances in 850 nm VCSELs for High-Speed Interconnects

“…After 44 years of development, remarkable progress has been made on the development of VCSELs, and many researchers have demonstrated ultra-fast VCSELs with modulation bandwidths of up to 30 GHz [22,[61][62][63][64][65]116]. Some of the selected works on 850 nm VCSELs are shown in Figure 16 and Table Y e a r Note: This table summarizes the maximum data rates and 3-dB bandwidths at RT (unless stated otherwise) reported in these manuscripts.…”

“…Valuable progress has been made in the development of devices and advanced modulation formats to enable high modulation responses and energy-efficient and rapid data transmission using VCSELs in the last few decades. Significant achievements have been made in the improvement of 850 nm VCSELs' modulation bandwidths, and the fastest reported 3 dB modulation bandwidth to date is ∼30 GHz [22,[61][62][63][64][65]116]. On the other hand, more work has to be done to standardize and commercialize these high-speed 850 nm VCSELs in commercial transceivers to enable the future 800 GbE and 1.6 TbE Ethernets.…”

“…In 2021, Chorchos et al from VI Systems GmbH (VIS) and the Warsaw University of Technology (WUT) reported a record 80 Gb/s using feed-forward equalization (FFE) technology with a 30 GHz VCSEL and BiCMOS driver packaged into a 33 GHz transceiver[61]. The latest reported 3 dB modulation bandwidth of an 850 nm VCSEL at RT was ∼30 GHz[22,[61][62][63][64][65], as they were close to the bandwidth limits of the VCSEL's intrinsic responses. For more efficient use of the VCSEL modulation bandwidths, the industry has moved toward other advanced modulation formats for 400 GbE, 800 GbE, and 1.6 TbE[35].…”

“…Figure16. Selected results for 3 dB bandwidths of nm VCSELs at RT (unless stated otherwise)[22,57,59,[61][62][63]65,81,83,[116][117][118][119][120][121][122][123][124][125][126][127][128][129][130][131][132][133].…”

Transverse Coupled Cavity VCSELs: Bridging Ultrabroadband Dynamics to Optical Supermodes

“…Focusing on the optical light source of the transmission block, vertical-cavity surfaceemitting lasers (VCSELs) have emerged as one of the most promising choices for high-speed low-power data communications, thanks to their compact active region, sub-mA threshold currents, and optimal packaging and coupling with optical fibers due to their circular symmetry [2]- [5]. While 100 Gbps bitrates can be still achieved with a combination of state-ofthe-art lasers [6], [7], complex modulation techniques such This work was supported in part by Cisco Systems, Inc., under the Sponsored Research Agreement MultiVCSEL, and in part by the European Union under two initiatives of the Italian National Recovery and Resilience Plan (NRRP) of NextGenerationEU: the partnership on Telecommunications of the Future (PE00000001 -program "RESTART"), and the National Centre for HPC, Big Data and Quantum Computing (CN00000013 -CUP E13C22000990001).…”