FieldLine Industries

FieldLine Industries builds scalar optically pumped magnetometers for the world outside the lab. Its flagship SM300 packs an atomic vapor cell just 4 millimeters across into a sensor small and light enough to mount on an uncrewed aerial system or embed in a submersible, aimed at magnetic anomaly detection, geological surveys, and space applications. The company operates from Louisville, Colorado, minutes from the Boulder atomic physics corridor that made microfabricated vapor cells a manufacturable product in the first place.

Its federal research trail runs through the SBIR program, with awards covering microfabricated vacuum-packaged rubidium vapor cells and standoff detection of hidden objects using tensor gradiometers, the kind of defense-adjacent sensing work that keeps quantum magnetometry funded between commercial orders.

One caution for readers: FieldLine Industries is a distinct entity from FieldLine, the Boulder company profiled separately here, whose optically pumped magnetometers target brain imaging rather than industrial and defense sensing. Same physics, different companies, different markets.