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.

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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.

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Russell and Xu's method starts with a sliced crystal, either sapphire or silicon, cut at an angle that exposes a ragged section of the crystal's lattice structure.

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If an electric charge is applied to the crystal, these holes and electrons will move in opposite directions, knocking into the lattice and creating more and more holes.

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