For both modes of crystal fibre, the pattern of holes is generated by stacking hollow glass tubes a millimetre or so in diameter to form a rod several centimetres thick.

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When passed through a crystal, the result is a pattern of spots which, if interpreted correctly, can be used to calculate the positions of the original atoms.

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Electrons, being waves as well as particles, produce a diffraction pattern when transmitted through a crystal.

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In the same way, the pattern of holes in a crystal fibre can create the equivalent for light of a graphite core and a diamond cladding.

ECONOMIST: A new approach to making optical fibres

The trick is to tune the crystal, by modifying the details of pattern, so that as much of the emitted energy as possible is at the frequency most efficiently captured by indium gallium arsenide.

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They then heated the crystal for 24 hours to up to 2, 700 degrees Fahrenheit--a process that forces the crystal surface to reorganize itself into a sawtooth pattern at three-nanometer intervals (at that breadth, 30, 000 such jagged edges side by side would be as wide as one human hair).

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Analysis of that pattern can tell you the details of how a crystal's atoms are arranged.

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This is the order of symmetry of the crystal (in other words, the number of ways it can be rotated to produce a pattern identical to the original).

ECONOMIST: The 2011 Nobel prizes