Energy Cascades in Quasicrystals Trigger an Avalanche of Discovery

Just as different pieces of glass come together along their edges to create shapes and patterns in a stained-glass window, a quasicrystal contains junctions that define its behavior. Although the junctions in a quasicrystal where different shapes come together can contain differing numbers of intersecting edges, each junction within a quasicrystal exhibits the same basic physical preference — to be in the lowest energy state possible. However, because each point within the quasicrystal is constantly interacting and competing with its neighbors, not all of the vertices can be in their lowest energy states at the same time.

In the experiment, the Argonne researchers wanted to see how the quasicrystal’s structure responded to adding some extra energy. “We were looking at whether we could actually transfer energy from one side of the lattice to the other, and to image the patterns that emerged when we tried to do so,” said Argonne materials scientist Charudatta Phatak, another author of the study.

To their surprise, the researchers discovered that the redistribution of energy through the quasicrystal took place as a chain reaction that resembled the forked branches of a lightning strike. Unlike in a more conventional magnetic lattice, where these “avalanches” of energy redistribution occur only a single direction, the spread of redistributed energy throughout the lattice takes on a tree-like appearance.

Quasicrystals could provide one example of a system that scientists have been looking for: a network made up of magnetic islands that can propagate and store information. The behavior of these kinds of networks depends upon the amount of energy that is put into the system, according to Phatak.

Understanding the energetic behaviors of these kinds of networks is essential for the development of next-generation computational devices that could form the foundation of things like artificial neural networks, which would be able to perform complex computations with very low energy consumption.

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