New study provides guide on how to make your own hyperuniform system

Introduced as a theoretical concept in 2003, hyperuniform systems—exotic amorphous states of matter that exhibit order over large distances and disorder over small distances—are being uncovered in a growing number of physics, chemistry, biology and ecology investigations. Spanning equilibrium and non-equilibrium phases as well as quantum and classical physics, examples range from photoreceptors in the chicken eye to disordered networks with large photonic band gaps.

Princeton chemist Salvatore Torquato, the theorist who coined the term hyperuniform systems with his colleague Frank Stillinger, believes that understanding of disordered many-particle hyperuniform systems has progressed to the point that even classical models of materials systems “should be re-examined with a hyperuniform lens.”

In Journal of Applied Physics in June 2017, Torquato and graduate student Zheng Ma provide compelling evidence for this advice. They explain how to create the hidden large-scale structural order that is the hallmark of hyperuniformity via Gaussian random scalar fields, which have been used to model the cosmic microwave background, heterogeneous materials, and many other systems. Their simulations also demonstrate hyperuniformity generated using the versatile Cahn-Hilliard equation, which describes the kinetics of how binary systems separate into two phases without the aid of a nucleation step. Freezing—or stopping—phase separation can yield a hyperuniform state, according to the simulation.

Similar results were obtained with the Swift-Hohenberg equation used in studies of emergent behavior and that describes thermal convection in hydrodynamics. Labyrinthine patterns that emerge as solutions to the equation are effectively hyperuniform.

“Novel structures yield novel properties,” says Torquato. He hopes his and Ma’s findings will guide experimentalists to synthesize new classes of hyperuniform materials, using such technologies as 3D printing and stereolithography.

Source: “Random scalar fields and hyperuniformity,” by Zheng Ma and Salvatore Torquato, Journal of Applied Physics (2017). The article can be accessed at https://doi.org/10.1063/1.4989492 .