In this compound, the tightly bound orbitals act like wells into which free electrons can fall, allowing the material to capture them more easily.

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To build their desktop Big Bang, the researchers arranged strips of acrylic and gold so that laser light hitting the gold excites waves of free electrons called plasmons.

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Normally, an incoming electron would have a good chance of displacing one of these low-energy incumbents, but unlike the free electrons in metals, which are usually singletons, those in a superconductor tend to wander around in pairs.

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The process of capture knocks electrons free inside the material and creates a current.

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The first knocked electrons free from their orbitals.

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Electrons in a metal are free to oscillate when light hits them.

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Crucially for data storage, this free flow means that the spins of the electrons in question would be able to align themselves with those of the data-storing atoms, giving a clean signal.

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What makes a free radical so reactive, however, is that unlike most molecules it has an odd number of electrons and electrons prefer to arrange themselves in pairs.

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