Lightmatter豪赌光而非铜，连接AI芯片——4.4亿美元估值融得4亿美元

做的是什么生意

Lightmatter builds photonic interconnect for AI data centers: its Passage system routes data between GPUs and racks over fiber at up to 30 Tbps, with roadmaps for photonic substrates and chiplets that put light next to the processor.

启动资金：$850M raised total; $400M Series D led by T. Rowe Price at a $4.4B valuation, with Fidelity and GV participating (TechCrunch).

起因

Lightmatter has been developing photonic chips since 2018 (TechCrunch). The bet follows a known ceiling: compute nodes keep getting faster, but clusters stall when data waits on electrical interconnects, and CEO Nick Harris argues hyperscalers cannot build million-node computers with traditional electrical switches (TechCrunch).

经过

Passage, Lightmatter's current interconnect, does 30 Tbps with up to 1,024 GPUs working synchronously in optical racks, and the company says hyperscalers are already customers though it will not name them (TechCrunch). The October 2024 Series D at $4.4B followed its mid-2023 raise and, per Harris, makes Lightmatter 'by far the largest photonics company.' In March 2025 it introduced a photonic interposer manufactured by GlobalFoundries, and a chiplet designed to sit atop AI chips, bringing optics into the package (Reuters via Economic Times).

结果

Still live and scaling: Passage is on the market with unnamed hyperscaler customers, and the company is expanding from rack-level interconnect toward in-package photonics, with an interposer planned for 2025 and a chiplet for 2026 (Reuters via Economic Times).

可借鉴之处

押注被忽视的环节：当芯片速度超过连接线时，互连成为瓶颈——而非芯片制造商Lightmatter凭借AI扩展难题获得8.5亿美元融资和44亿美元估值。