At its last earnings conference, Coherent brought up “200-gig VCSEL-based 1.6T transceivers ramping in the second half of this calendar year” (please see: https://lnkd.in/eJETqkmi), albeit putting an emphasis on CPO and MPO apps (please see: https://lnkd.in/eQ6uVt2p). At least right now, the opportunities for those devices at that rate, especially in the west, appear to be substantially lower than what occurred at 100G per lane.
As the major hypersclalers moved away from reliance on multimode fibers, the potential for significant demand was mainly at the mercy of Nvidia (please see: https://lnkd.in/dbN9zdF6). It turns out that the supplier, like those large users, decided against planning to employ 200G VCSELs for 1.6T MM optics modules.
In fact, it is fibeReality’s understanding that Nvidia even designated the 100G VCSEL-based solution for scale-out as “end of life” because of the problem with link flapping. Although there is still at least theoretically a market for VCSELs, involving short reach with active optical cables, the bad news is that with scale-up, the requirement is even more demanding, with the bit error rate higher than for silicon photonics (please see: https://lnkd.in/eXCmm5g5). Therefore, it seems that the main, current opportunity for sales of 200G VCSELs, presumably also effecting Broadcom, which excels at making bare die for those products, could seemingly be for cloud usage in China, probably not large in size (please see: https://lnkd.in/eSvw4eJa).
Furthermore, the presently most optimistically new play for VCSELs would be for slow and wide, 50G-NRZ deployment (please see: https://lnkd.in/eSVdfH-b). The way it has been characterized to fibeReality by a large end-user, is in possibly utilizing a “micro-VCSEL.”
In general, though, just as the case with NRZ, one should still be careful about quickly throwing in the towel on the future of what was a short time ago, considered to be a critically important, low-cost network element. There has been movement (including standards work) in the direction of developing VCSELs up to 50 meters at the 200G rate and at the 1060nm wavelength for scale-up, requiring a new fiber with sufficiently high EMB to reach at least 30 meters.