The new Roundhill Photonics and Optics ETF (LYTE) aims to capitalize on the growing demand for optical networking in AI data centers, which uses light pulses for faster, more energy-efficient data transmission. Roundhill's previous Memory ETF (DRAM), launched in April, amassed tens of billions of dollars in record time. Nvidia has invested at least $6.5 billion in photonics companies and plans to release its Feynman GPU microarchitecture, pivoting to photonics, in 2028. Goldman Sachs projects the optical networking market to grow over ninefold from $15 billion to $154 billion between 2026 and 2028.