Challenge to Find Quasicrystals with Seven-Fold Symmetry
نویسنده
چکیده
Recently, Dan Shechtman was awarded the Nobel-Prize for his 1984 discovery of a quasicrystalline phase with five-fold symmetry [1] in a sputtered Al-Mn alloy. While the solid-state community considered this discovery initially with great skepticism [2], as is now vividly described in many newspaper articles and in Shechtman’s Wikipedia page [3], the existence of material with such a symmetry had been proposed three years earlier by Kleinert and Maki in 1981 [4]. In that paper, an extremely simple order parameter was composed of a sum of exponentials
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