Periodic Polymeric Materials: Deaf and Blind Structures

技术综述亚微米和纳米尺度的周期性和准周期性聚合物结构为在这些长度尺度上进行材料行为的基础研究提供了许多有趣的科学机会。该方案描述了一种可同时作为高超声速声子晶体和可见光波长光子晶体的周期性聚合物材料的实验研究和理论模拟的统一方法。结构将使用嵌段聚合物自组装和干涉以及电子束光刻来制造。我们计划探索通过双反转技术以及用独特的有机-无机杂化单体直接制备的新型光子带隙结构。对于声子色散关系的直接实验测量，布里渊光散射是一种理想的方法，而入射光的透射率和反射率将被用来评估光学色散关系。有限元模拟提供了模拟弹性波在大范围的双分量周期结构中传播的能力，而数值技术已经被很好地用于模拟光波的传播。这些工具和方法的组合构成了一套完整的方法，用于这一令人兴奋的新材料的制造和表征、测量和建模。非技术总结声光两种带隙材料(聋盲材料？)是朝着创造具有不同寻常性质的材料系统迈出的一步。目前努力的成功将为构建多组分、分层结构的材料提供一条前进的道路，该材料旨在提供一组关键特性。这项工作将帮助我们理解光和声通过纳米结构聚合物材料传播的基本性质。这项工作有望增强声子、光子以及重要的双带隙光子-声子晶体的实验研究的基础，并为实现新的材料特性(例如定制的热导率、显著增强的声光耦合)开辟新的途径，这些新的材料特性可以具有重要的技术应用，因为周期性结构材料的特性不再仅仅是由于固有的材料特性，而是可以由结构内的波干涉的作用来支配，以获得以其他方式根本无法获得的新颖的和实际上是革命性的特性(例如，声音和光在材料中的特定位置的局域化)。我们的努力将开发实验技术和熟练的人才，以便在真正新兴的周期性材料新领域的尖端使用它们。此外，与声波和光波合作是激发年轻人对科学奇迹的巨大优势。这是因为光波和声波无处不在吗？我们基本上每天都沉浸在它们之中，不断地接收和发送这样的浪潮。这些波与周期结构的非直觉相互作用引起了真正的敬畏。我们计划在基板上提供嵌段共聚物薄膜，这些薄膜可以很容易地被厨房化学操纵。使用各种刺激物，如醋和盐溶液。我们的兴趣是向学生介绍波与微纳尺度上的周期性结构材料相互作用的有趣方式，以创造新的性质，并高调/激励一年级数学中的某些主题的研究，包括傅立叶级数，我们刚刚完成了一本专著《周期性材料与干涉光刻：光子学、声子学和力学》，？将于2008年夏季由Wiley-VCH出版。

TECHNICAL SUMMARYPeriodic and quasiperiodic polymeric structures at the sub-micron and nano scale offer many interesting scientific opportunities for fundamental studies of material behavior at these length scales. This proposal describes a unified approach for the experimental investigation and theoretical modeling of periodic polymer materials which can simultaneously act as hypersonic phononic crystals and visible wavelength photonic crystals. Structures will be fabricated using block polymer self-assembly and interference and electron beam lithography. We plan to explore novel photonic bandgap structures fabricated via double inversion techniques as well as through direct fabrication with unique organic-inorganic hybrid monomers. Brillouin light scattering is an ideally suited method for the direct experimental measurement of phonon dispersion relations while transmission and reflection measurements of incident light will be employed to assess the optical dispersion relations. FEM modeling provides the ability to model elastic wave propagation in a wide range of bicomponent periodic structures and numerical techniques are well established for modeling light wave propagation. The combination of these tools and approaches constitutes a complete methodology for fabrication and characterization, measurement and modeling of this exciting new class of materials. NON-TECHNICAL SUMMARYDual band gap materials for sound and light (?Deaf and Blind Materials?) are a step towards creation of material systems with unusual properties. Success in the present endeavor will provide a pathway forward for construction of multicomponent, hierarchically structured materials designed to provide a set of key properties. This work will help us understand the basic nature of the propagation of light and sound through nanostructured polymeric materials. This work promises to enhance the foundations for experimental studies of phononic, photonic and importantly dual band gap photonic-phononic crystals and open new pathways towards achieving new material properties (e.g.tailored thermal conductivity, significantly enhanced acousto-optical coupling) that can have important technological applications since the properties of the periodically structured material are no longer just due to the inherent material properties, but can be dominated by the role of wave interference within the structure to give novel and indeed revolutionary properties (e.g. localization of sound and light to specific places in the material) that are simply unattainable otherwise. Our efforts will develop both experimental techniques and skilled people to use them at the cutting edge of what is really the emerging new field of ?periodic materials.?Moreover, working with sound and light waves is a tremendous advantage for inspiring young minds to the wonders of science. This is because light waves and sound waves are ubiquitous ? we are essentially immersed in them every day and are continually receiving and sending such waves. The non-intuitive interactions of these waves with periodic structures elicits genuine awe. We plan to provide block copolymer films on substrates that can be readily manipulated by ?kitchen chemistry? using various stimuli such as vinegar and salt solutions. Motivated by our interests to introduce students to the interesting ways that waves interact with periodically structured materials at the micro- and nano- scale to create new properties as well as to highlite/motivate the study of certain topics in freshman year math, including Fourier series, we have just completed a monograph, ?Periodic Materials and Interference Lithography: photonics, phononics and mechanics,? to be published in summer, 2008 by Wiley-VCH.