They consist of two interlaced materials that have different optical properties in particular, different refractive indices, a measure of how much a substance bends light.

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Why that is so lies buried in the different crystalline structures of the two materials.

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LEDs function by driving electrons across a junction between two semiconductor materials in which electrons move at different energy levels.

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Second, disruptive new business models are overwhelmingly likely to be hybrids that bring together at least two different innovations in areas that include product design, supply chain organization, retailing models, materials science research, manufacturing and organizational effectiveness.

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