Roundhill’s photonics ETF LYTE pulls $72M in first-day volume as Wall Street’s AI hardware bet intensifies

Roundhill Investments just dropped another hyper-targeted tech ETF, and the market showed up with its wallet open. The Roundhill Photonics & Optics ETF, trading under the ticker LYTE, pulled in $72 million in trading volume on its first day, August 6, 2026. That figure topped the opening-day volume of Roundhill’s own Memory ETF (DRAM), which has since become one of the most successful thematic ETF launches in recent history. What LYTE actually holds and why it matters LYTE is about as concentrated as ETFs get. The fund holds just 12 positions, all focused on companies operating in the photonics and optics space. Think lasers, fiber optic components, optical networking gear: the physical layer that makes data move through AI-era data centers at the speed these workloads demand. The fund carries an expense ratio of 0.65%, which is on the higher end for an ETF but fairly standard for thematic products targeting niche sectors. It began trading on the Cboe BZX exchange. Roundhill wasn’t even first to this particular thesis. Tema launched its own photonics ETF, LAZR, on June 30, 2026, making LYTE the second dedicated fund in the space. The DRAM playbook and why it keeps working To un...