That is good news: defects in the crystal, unlike ambient temperature, can be fixed.

ECONOMIST: MONITOR

This weakness is caused by defects forming in their crystal-lattice structure, which in turn are caused by high-energy particles such as neutrons bumping into individual atoms and knocking them out of place.

ECONOMIST: New materials for renewable energy

It could be defects due to missing atoms, thermal vibrations of the crystal lattice, or even the boundaries between small, imperfectly formed crystals that make up the material.

ECONOMIST: MONITOR