Researchers at Duke University have for the first time demonstrated the design and construction of a thin metamaterial that can control the redirection and reflection of sound waves with almost perfect efficiency, that is quickly and easily fabricated using 3-D printers.

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Researchers at Duke University have for the first time demonstrated the design and construction of a thin metamaterial that can control the redirection and reflection of sound waves with almost perfect efficiency, that is quickly and easily fabricated using 3-D printers.