IMR: Acquisition of Optical Instrumentation for Determination of the Band Structure of Photonic and Phononic Crystals and Education of Students

本项目旨在构建两种光学仪器，以测量周期性高分子材料的新型光学和声学特性。麻省理工学院的科学家们特别感兴趣的是使用高分辨率磁光旋转测量和布里渊光散射来测量自组装嵌段共聚物和光聚合物中的光子和声子色散关系。这两种互补的测量类型共同依赖于共同的物理（周期性介质中的波传播）。具体而言，研究人员将构建一个由电磁铁系统和光弹性调制器组成的高分辨率法拉第极化旋转装置用于磁光测量，并购买一个由法布里-珀罗干涉仪和雪崩光电探测器组成的布里频光散射装置，以实现声子色散曲线的测量。这些实验装置的实现将使科学家们能够测试最近在NSF资助DMR#0308133下进行的关于含有磁光纳米粒子的一维手性光子晶体的建模研究中非常令人兴奋的预测，并进一步研究通过干涉光刻制成的一维层状嵌段共聚物晶体和三维双连续立方网络晶体中的声子色散。科学家们发现了一种与机械性能周期性变化相关的非色散类光学模式，这清楚地表明了声子晶体的行为。光子晶体（可以引导光的传播，特别是反射某些颜色的材料）和声子晶体（可以引导声音的传播，特别是反射某些频率的材料）都是基础科学和潜在的技术上非常有趣的材料。在这个项目中，麻省理工学院的科学家们将开发两种相关的仪器来对这些有趣的现象进行新的测量。周期性材料中电磁波（光）或弹性波（声）之间的相互作用可能是令人惊讶和有用的。研究人员将制作合适的聚合物晶体图案，使用完善的理论模拟其特性，并使用新获得的仪器获取从未测量过的数据，以对理论进行关键比较，并对潜在的革命性新设备进行基本见解：超薄棱镜传播白光的颜色，以及人们可以看到但听不到的开放结构。

This project is aimed at constructing two optical instruments in order to measure novel optical and acoustic properties of periodic polymeric materials. Specifically scientists at the MIT are interested in measuring both photonic and phononic dispersion relationships in self assembled block copolymers and photopolymers created by 3d interference lithography using high resolution magnetooptical rotation measurements and Brillouin light scattering. These two complementary types of measurement jointly rely on common physics (wave propagation in periodic media). Specifically the researchers will construct a high resolution Faraday polarization rotation apparatus comprised of an electromagnet system and a photoelastic modulator for the magnetooptical measurements and purchase a Brillouin light scattering apparatus, consisting of a Fabry-Perot interferometer and avalanche photodetector to enable the phononic dispersion curves to be measured. The realization of such experimental setups will enable scientists to test very exciting predictions of recent modeling studies conducted concerning 1D chiral photonic crystals containing magnetooptical nanoparticles being performed under NSF grant DMR#0308133 and to further recent work on phonon dispersion in 1D lamellar block copolymer crystals and 3d bicontinuous cubic network crystals made via interference lithography. The scientists have found a nondispersive optic-like mode related to the periodic variations in the mechanical properties, a clear indication of the behavior of a phononic crystal. Photonic crystals (materials that can guide the propagation of light, and in particular reflect certain colors) and phononic crystals (materials that can guide the propagation of sound, and in particular, reflect certain frequencies) both present basic scientific and potentially very technologically interesting materials. In this project scientsists at MIT will develop two related instruments to make new measurements of these interesting phenomena. Interactions between electromagnetic waves (light) or elastic waves (sound) in periodic materials can be surprising and useful. The researchers will make appropriate patterned polymeric crystals, model/simulate their properties using well developed theories and use the newly acquired instruments to access never before measured data for critical comparison to theory and for fundamental insight into to potentially revolutionary new devices: super thin prisms to spread out the colors of white light and open structures that one can see through but not hear through.