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

本项目的目的是构建两个光学仪器，以测量周期性聚合物材料的新型光学和声学性质。具体地说，麻省理工学院的科学家们感兴趣的是利用高分辨率磁光旋转测量和布里渊光散射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。这两种互补类型的测量共同依赖于共同的物理学(波在周期介质中的传播)。具体地说，研究人员将建造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偏振旋转装置来进行磁光测量，并购买一个布里渊光散射仪，由法布里-珀罗涉仪和雪崩光电探测器组成，以便能够测量声子色散曲线。这些实验装置的实现将使科学家能够检验最近进行的非常令人兴奋的预测，这些建模研究是在美国国家科学基金会的DMR#0308133号拨款下进行的，涉及含有磁光纳米颗粒的一维手性光子晶体，并进一步研究了通过干涉光刻制作的一维层状嵌段共聚物晶体和三维双连续立方体网络晶体中的声子色散。科学家们发现了一种与机械性能的周期性变化有关的非色散类光学模式，这是声子晶体行为的明确指示。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)都是基本的科学材料，而且可能是非常有技术意义的材料。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。周期性材料中的电磁波(光)或弹性波(声)之间的相互作用可能是令人惊讶和有用的。研究人员将制造适当的图案化聚合物晶体，使用成熟的理论对其性质进行建模/模拟，并使用新获得的仪器获取前所未有的测量数据，以便与理论进行关键比较，并从根本上洞察潜在的革命性新设备：超薄棱镜可以展开白光的颜色，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.