CAREER: Adaptive Photonic Polymers

与通过影响电子流来控制信息的电子设备不同，光子设备通过影响光子或光的流动来控制信息，并且具有克服电子设备的速度和带宽的潜力。光子器件的关键是它们的基本成分——光子晶体，光子晶体是由高介电常数和低介电常数有规律重复的区域组成的周期性纳米结构。由于在交替介电域之间的界面处的多次反射，阻止了光通过这种晶体的传输；当波长与特征域尺寸相当时，就会发生这种情况。然而，大多数现有光子晶体的带隙不能被主动控制，因为一旦纳米结构形成，其畴大小就不能改变。在自适应光子晶体的发展中，如何实现光的按需控制仍然是一个挑战。该项目旨在建立设计和制造自适应光子聚合物所需的基础知识——聚合物光子晶体能够主动控制可见光和红外光。在教育方面，除了为研究生、本科生和来自不同背景的高中生提供研究机会外，本课程所考虑的主题将整合到新开发的课程“高级聚合物”中。该项目还包括一些外联活动。本研究计划旨在建立自适应光子聚合物的分子-微观结构-性能-功能关系-聚合物光子晶体，使光的按需控制成为可能。研究的核心假设是，利用结构设计的嵌段共聚物的自组装，可以使具有超大特征长度的周期性介电纳米结构具有响应性，这是操纵宽波长范围光所必需的。PI的工作将侧重于：(i)开发具有极端分子结构（如大直径和高分子量）的嵌段共聚物的受控合成方法；（ii）确定聚合物形成可见光和红外光所需的大特征长度的远程有序纳米结构的分子结构；(3)建立微观结构与宏观光学性质之间的因果关系；（iv）使用定制开发的原位表征技术量化光学特性对外部刺激的响应。实验研究将通过标度理论和自洽场理论模拟得到证实。利用通过这些研究获得的基本理解和开发的技术，将演示使用一种自适应光子聚合物对可见光和红外光的主动快速控制。本研究将整合到研究生、本科生和6-12年级的实验室和课堂的各种教育经验中。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

PART 1: NON-TECHNICAL SUMMARYUnlike electronic devices that control information by affecting the flow of electrons, photonic devices control information by affecting the flow of photons or light and have the potential to overcome the speed and bandwidth of electronic devices. Key to photonic devices is their basic components -- photonic crystals, which are periodic nanostructures consisting of regularly repeating regions of high and low dielectric constants. Transmission of light through such a crystal is prevented due to multiple reflections at the interfaces between alternating dielectric domains; this occurs when the wavelength is comparable to characteristic domain sizes. The band gaps of most existing photonic crystals, however, cannot be actively controlled because once a nanostructure is formed, its domain size cannot be changed. It remains a challenge in the development of adaptive photonic crystals to control light on-demand. This project aims to establish the foundational knowledge required to design and create Adaptive Photonic Polymers -- polymeric photonic crystals that enable active control of visible and infrared light. Educationally, in addition to providing research opportunities for graduate students, undergraduates, and high school students from diverse backgrounds, the topics considered in this program will be integrated into a newly developed course, "Advanced Polymers." The project also incorporates a number of outreach activities.PART 2: TECHNICAL SUMMARYThis research program aims to establish the molecule-microstructure-property-function relation for Adaptive Photonic Polymers -- polymeric photonic crystals that enable on-demand control of light. The central hypothesis is that exploiting the self-assembly of architecturally designed block copolymers enables responsive periodic dielectric nanostructures with exceptionally large characteristic lengths necessary for manipulating light of a wide range of wavelengths. The PI's work will focus on: (i) development of methods for controlled synthesis of block copolymers with extreme molecular architecture such as large diameter and high molecular weight; (ii) determining the molecular architecture for which the polymers form long-range, ordered nanostructures of large characteristic lengths necessary for visible and infrared light; (iii) establishing the causal relation between microstructure and macroscopic optical properties; (iv) quantifying the response of optical properties to external stimuli using custom-developed in-situ characterization techniques. The experimental studies will be corroborated by scaling theory and self-consistent field theoretical simulations. Using the fundamental understanding gained and the technologies developed through these studies, active fast control of visible and infrared light will be demonstrated using one Adaptive Photonic Polymer. This research will be integrated into a variety of educational experiences in the laboratory and the classroom at the graduate, undergraduate, and 6-12 levels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.