Broadcom, Lumentum post strong AI earnings; optical infrastructure emerges as critical chokepoint

Both Broadcom and Lumentum have benefited from a shared tailwind: the explosive scaling of AI infrastructure requires solving a physical bottleneck in data center architecture. Traditional copper interconnects are constrained by heat dissipation, power delivery, and distance limits when connecting racks at scale. Optical solutions—light-based transmission—bypass these constraints, which is why optics has moved from a niche to a central part of the AI buildout.

Broadcom and Lumentum serve this opportunity at different points in the supply chain. Broadcom is the systems integrator, building the full stack of custom silicon and switching fabrics that AI hyperscalers (large cloud providers) deploy. Lumentum is the component supplier, providing the optical engines that Broadcom and competitors embed into their switches and modules. This structural difference means the two companies have very different risk profiles: Broadcom has diversification (VMware, Ethernet for non-AI use cases) and a $0.65 quarterly dividend, while Lumentum has concentrated exposure to the optical bottleneck but also tighter margin expansion and faster revenue growth from a smaller base.

The near-term test for both is execution at scale. Broadcom must deliver its Q3 guidance ($16.0 billion AI semi revenue, growing over 200% YoY) while keeping VMware cash flow intact. Lumentum must ramp its OCS backlog (over $400 million) and deliver a multi-hundred-million-dollar CPO order in 1H CY2027 without slipping. Polymarket traders assign a 74% probability to Broadcom clearing its Q3 AI revenue bar, suggesting high confidence in the near term, though both stocks have already priced in substantial good news.