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arXiv · 2312.08541

Emergence of Disordered Hyperuniformity in Melts of Linear Diblock Copolymers

Abstract

Disordered hyperuniform (DHU) systems are recently discovered exotic states of matter, where (normalized) large-scale density fluctuations are completely suppressed as in crystals, even though the systems are isotropic and lack conventional long-range order. Despite recent success, realizing such systems using bottom-up approaches remains challenging. Here, we study the large-scale behavior of neat melts of linear diblock copolymers using large-cell self-consistent field theory (SCFT) simulations. We initialize SCFT simulations using point patterns that correspond to the local energy minimum of the so-called Quantizer energy, a geometric functional related to the free energy of copolymeric self-assemblies. Upon relaxation via the SCFT simulations, we obtain a new class of metastable disordered micelle mesophases that are hyperuniform. Moreover, we find that DHU micelle mesophases possess very similar free energies to the thermodynamically stable body-centered cubic sphere mesophases and are also much more favorable energetically than previously obtained liquid-like packings. Our findings shed light on the design of novel disordered hyperuniform materials using bottom-up approaches, and suggest new possibilities for technological applications, e.g., novel non-iridescent structural colors.

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Duyu Chen, Michael A. Klatt, Glenn H. Fredrickson. 2024-03-22. Emergence of Disordered Hyperuniformity in Melts of Linear Diblock Copolymers. https://arxiv.org/abs/2312.08541

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