RTX Ventures Invests in Xcimer Energy, Teams Up on Laser Directed-Energy Defense Tech

RTX Ventures, the venture arm of defense contractor RTX, announced on September 10, 2026 a minority investment in laser-fusion company Xcimer Energy alongside a teaming agreement to explore integrating Xcimer's multi-kilojoule-class pulsed-laser technology into RTX directed-energy defense systems aimed at destroying drones, missiles, and other airborne threats. Xcimer's excimer laser platform — the basis for its DOE-approved Athena fusion power plant design (approved June 10, 2026) — shares core engineering challenges with laser weapons: firing pulses repeatedly, reliably, and affordably at scale. Xcimer has raised roughly $200M to date from investors including Hedosophia and Breakthrough Energy Ventures, and is targeting grid fusion power in the mid-2030s. The investment amount was not disclosed.