Yes. Nato is has been testing the Watchment muon detection system that was designed to track nuclear material, specifically looking for nuclear submarines.
Another one along these lines is antineutrinos. They're created by fission reactions, so a nuclear reactor puts out a lot of them. From what's available in the open literature, this seems like it might be getting close to being practical.
https://thedebrief.org/darpas-secretive-new-neutrino-detecto...