Defect-Free Growth of Decagonal Quasicrystals around Obstacles
Kelly L Wang1, Insung Han2, Domagoj Fijan3
1University of Michigan, Macromolecular Science and Engineering Program, Ann Arbor, Michigan 48109, USA.
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Quasicrystals are aperiodic solids with exotic physical properties. The mechanisms driving their growth are far from understood, particularly in the presence of rigid obstacles. Using in situ synchrotron x-ray tomography and molecular dynamics simulations, we investigate the interaction between decagonal quasicrystals and obstacles (shrinkage pores) during solidification of an Al_{79}Co_{6}Ni_{15} alloy. The results reveal defect-free quasicrystal growth around the pores, independent of pore size and geometry. Our findings point to a universal feature of aperiodic solids: their ability to accommodate structural disruptions due to additional (phasonic) degrees of freedom. This Letter opens new possibilities for synthesizing large-scale, single quasicrystals from a liquid metal precursor.
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