Hyperuniform monocrystalline structures by spinodal solid-state dewetting

TL;DR

This paper demonstrates a scalable bottom-up method to create hyperuniform disordered structures in monocrystalline semiconductor layers through spinodal solid-state dewetting, enabling new applications in photonics and electronics.

Contribution

It introduces a novel approach using spinodal dewetting of SiGe layers to produce hyperuniform disordered structures in a scalable manner.

Findings

Successful fabrication of hyperuniform structures via spinodal dewetting.

Simulation insights into pattern formation dynamics.

Potential for scalable production of hyperuniform metamaterials.

Abstract

Materials featuring anomalous suppression of density fluctuations over large length scales are emerging systems known as disordered hyperuniform. The underlying hidden order renders them appealing for several applications, such as light management and topologically protected electronic states. These applications require scalable fabrication, which is hard to achieve with available top-down approaches. Theoretically, it is known that spinodal decomposition can lead to disordered hyperuniform architectures. Spontaneous formation of stable patterns could thus be a viable path for the bottom-up fabrication of these materials. Here we show that mono-crystalline semiconductor-based structures, in particular Si$_{1-x}$Ge$_{x}$ layers deposited on silicon-on-insulator substrates, can undergo spinodal solid-state dewetting featuring correlated disorder with an effective hyperuniform character. Nano- to micro-metric sized structures targeting specific morphologies and hyperuniform character can be obtained, proving the generality of the approach and paving the way for technological applications of disordered hyperuniform metamaterials. Phase-field simulations explain the underlying non-linear dynamics and the physical origin of the emerging patterns.