$LYTE vs $PHOX

The short version

PHOX is cheaper to own, at 0.60% a year versus 0.65%. LYTE is the bigger fund, with $343M in assets. LYTE has been around longer, launching on August 6, 2026.

LYTE

The Roundhill Photonics & Optics ETF focuses on the optical side of the AI infrastructure build: optical interconnects, lasers and photonic chips that move data with light inside AI data centers. At launch its top holdings included Lumentum, Coherent, Ciena and Fabrinet, plus China-listed optical module makers such as Eoptolink and Zhongji Innolight. A concentrated top ten and a large weight in China-listed optical module makers mean LYTE can move very differently from a broad semiconductor fund. Position sizes can change quickly in an actively managed fund.

PHOX

The Aura AI Photonics ETF tracks the VettaFi AI Photonics Index, a basket of roughly 25 global companies involved in generating, transmitting and processing data with light for AI computing: lasers, transceivers, photonic integrated circuits and specialty materials such as indium phosphide. As an index fund, PHOX follows set rules rather than a manager's calls, which makes it easier to know what you own. It is still a small, non-diversified, single-theme fund, so expect big swings.

Lower fees and more assets are helpful, but they are not the whole story. The bigger question is which strategy matches what you want to own. This comparison is not a recommendation to buy or sell either fund.