Contamination-Free, Lightweight, Helium-Rubidium Vapor Circulation System

Diode-Pumped Alkali Laser Systems (DPALS) have great potential for missile defense and other applications. These systems require a uniform, steady, flowing mixture of helium and rubidium vapor at elevated pressure and temperature. Significant challenges exist because rubidium is a very reactive material. In response, our team proposes to develop a contamination-free, all-metal, hermetic, circulation system based on gas-bearing turbomachines we have developed for space-based applications with operating temperatures up to 780°C. Specific benefits include low mass, compact volume, zero maintenance, high reliability, and long life. The approach is also modular and scalable with current technology appropriate for significantly smaller and larger flow rates than currently requested by MDA. Our team is well-suited to succeed because we have a long history developing advanced thermodynamic systems for challenging aerospace applications, core technology elements are mature from prior work, we have high-level laser expertise to ensure design details are relevant for DPALS, and we have extensive experience with alkali metal reactivity and compatibility. During Phase I, we will optimize design trades, complete a preliminary design, and conduct rubidium vapor tests. We will then fabricate and test a prototype circulation system during Phase II.