Helium-3 in Neutron Detection

Helium-3 is the gold-standard gas for detecting neutrons — a homeland-security and scientific need that competes with quantum computing for the same scarce isotope.

In brief

• He-3 has a large neutron-capture cross-section, making efficient, low-background detectors.
• Used at ports and borders for radiation screening.
• The same supply feeds quantum cryogenics — hence the competition.
• Kronos supply eases both demands.

The detail

Helium-3 proportional counters are the benchmark for thermal-neutron detection, valued for sensitivity and gamma rejection. Their deployment in security screening was a major driver of the post-2009 supply squeeze — the same squeeze now felt by the quantum industry.