A chameleon can alter the color of its skin by using periodic optical nanostructures, called photonic crystals, in its skin. So far, scientists have made versions of a photonic crystal "smart skin" that changes color in response to the environment, but the sizes of these versions of “smart skin” also change. This time, chemists at Emory University have developed a flexible smart skin that reacts to heat and sunlight while maintaining a near constant volume.
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