Harvard engineers have a devised a technique for designing and producing intricate microscopic models, called "hierarchical microarchitectures," and the tiny sculptures it produces are nothing short of incredible.
The flowers sprout up spontaneously when a glass plate is dipped into a beaker filled with silicon and minerals (specifically, barium chloride). Then Wim Noorduin at Harvard coaxes the salts to spiral and swirl into smooth, curvaceous shapes, like vases, leaves and petals.
He sculpts the stems and blossoms by slightly tweaking the environment in which the crystals grow. Lowering the temperature makes the petals thicker. Bursts of carbon dioxide send ripples through the leaves and blossoms.
The result, writes Noorduin in the latest issue of Science, is "a bouquet of hierarchically assembled multiscale microstructures with unprecedented levels of complexity and precision." For a sense of scale, here are some of Noorduin's microflower sculptures lining the steps of the Lincoln Memorial, imprinted on the back of a penny:
But flowers are just the beginning. The ability to design and guide the fabrication of nanoscale structures in a manner similar to 3D-printing has enormous ramifications for fields ranging from optics to electronics.
For more info, and more pictures, visit NPR.