Soft quasicrystals - Why are they stable?

TL;DR

This paper reviews the recent discovery of soft quasicrystals in soft matter, emphasizing their stability possibly due to two natural length-scales and three-body interactions, and discusses their fundamental and application potentials.

Contribution

It proposes a theoretical explanation for the stability of soft quasicrystals based on two length-scales and three-body interactions, advancing understanding of their formation.

Findings

Existence of soft quasicrystals in soft matter systems

Two natural length-scales contribute to their stability

Three-body interactions are key to their formation

Abstract

In the last two years we have witnessed the exciting experimental discovery of soft matter with nontrivial quasiperiodic long-range order - a new form of matter termed a soft quasicrystal. Two groups have independently discovered such order in soft matter: Zeng et al. [Nature 428 (2004) 157] in a system of dendrimer liquid crystals; and Takano et al. [J. Polym. Sci. Polym. Phys. 43 (2005) 2427] in a system of ABC star-shaped polymers. These newly discovered soft quasicrystals not only provide exciting platforms for the fundamental study of both quasicrystals and of soft matter, but also hold the promise for new applications based on self-assembled nanomaterials with unique physical properties that take advantage of the quasiperiodicity, such as complete and isotropic photonic band-gap materials. Here we provide a concise review of the emerging field of soft quasicrystals, suggesting that the existence of two natural length-scales, along with 3-body interactions, may constitute the underlying source of their stability.