Complete Photonic Band Gaps with Nonfrustrated ABC Bottlebrush Block Polymers
Complete Photonic Band Gaps with Nonfrustrated ABC Bottlebrush Block Polymers
复制标题
使用非受阻 ABC Bottlebrush 嵌段聚合物实现完整的光子带隙
DOI：
10.1021/acsmacrolett.0c00380
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发表时间：
2020
影响因子：
7.015
通讯作者：
Fredrickson, Glenn H.
中科院分区：
文献类型：
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作者：
Lequieu, Joshua;Quah, Timothy;Delaney, Kris T.;Fredrickson, Glenn H.
瓶刷嵌段聚合物是一种很有前途的自组装光子材料平台，但大多数工作仅限于基于片层相的一维光子晶体。在这里，我们通过模拟证明，无挫败的ABC瓶刷嵌段聚合物可以用来自组装具有完全光子带隙的三维光子晶体。为了证明这一点，我们开发了一种计算方法，将自洽场理论(SCFT)模拟耦合到麦克斯韦方程，从而允许分子设计、自组装和光子能带结构之间的直接联系。使用这种方法，我们计算了非受挫ABC瓶刷嵌段聚合物的相图，并确定了交替回转和交替金刚石相稳定的区域。通过计算这些相的光子能带结构，我们证明了在热力学稳定区可以找到完全的带隙，从而为这些光子材料的实验实现提供了一条途径。此外，我们证明了带隙大小取决于体积分数、偏析强度和聚合物结构，并确定了一种基于对称性破缺的设计策略，该策略可以在较低的折射率对比度下实现带隙。综上所述，本文提出的方法为预测聚合物材料的自组装和光子能带结构提供了一个强大而灵活的工具。
Bottlebrush block polymers are a promising platform for self-assembled photonic materials, yet most work has been limited to one-dimensional photonic crystals based on the lamellar phase. Here we demonstrate with simulation that nonfrustrated ABC bottlebrush block polymers can be used to self-assemble three-dimensional photonic crystals with complete photonic band gaps. To show this, we have developed a computational approach that couples self-consistent field theory (SCFT) simulations to Maxwell’s equations, thereby permitting a direct link between molecular design, self-assembly, and photonic band structures. Using this approach, we calculate the phase diagram of nonfrustrated ABC bottlebrush block polymers and identify regions where the alternating gyroid and alternating diamond phases are stable. By computing the photonic band structures of these phases, we demonstrate that complete band gaps can be found in regions of thermodynamic stability, thereby suggesting a route to realize these photonic materials experimentally. Furthermore, we demonstrate that gap size depends on volume fraction, segregation strength, and polymer architecture, and we identify a design strategy based on symmetry breaking that can achieve band gaps for lower values of refractive index contrast. Taken together, the approach presented here provides a powerful and flexible tool for predicting both the self-assembly and photonic band structures of polymeric materials.