Collaborative Research: Science and Engineering of Topological Acoustics and Mechanics

合作研究：拓扑声学与力学科学与工程

• 批准号: 1537294
• 负责人: Alexander Khanikaev
• 金额: $ 22.7万
• 依托单位: CUNY Queens College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2016-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1537294&HistoricalAwards=false
• 关键词: Collaborative; Research; Science; Engineering; Topological

Propagation, interference and scattering are basic manifestations of the wave nature of acoustic and other mechanical waves. For centuries, humans have used these properties to control and manipulate sound to a certain degree, for instance to realize musical instruments, music halls and whispering galleries. However, a new principle of organization of matter based on advanced topological concepts has been recently discovered in condensed matter physics. Scientists working in different branches of physics and engineering are motivated by these concepts. By exploiting topological constraints in the dispersion of suitably engineered composite material systems, it is possible to realize highly nonlocal responses with unusual stability to perturbations in their wave propagation characteristics. The aim of this project is to translating these concepts to acoustic and mechanical systems. The goals are to redefine the understanding of wave phenomena and to dramatically expand the ability to manipulate mechanical and acoustic waves. Results from this research will expand the engineering toolkit, improving the architecture of mechanical and acoustic devices, for instance by reducing undesirable interactions between different components, including transducers, receivers, and resonant elements. This approach will endow mechanical wave propagation with topological protection, enabling one-way guiding along arbitrarily shaped pathways without back-reflection, and making it robust to defects and disorder. Since this project bridges several disciplines, including material science, physics and engineering, its multi-disciplinary character will have positive educational impact. The project will widen the background and improve the preparation of students involved into this project, and, due to the broad overlap with diverse disciplines, including engineering of music and sound, it will broaden participation of underrepresented minorities in research and education.The idea of applying the concepts of topological order to sound and mechanical waves opens venues in a multitude of scientific fields of research, from basic science to applied physics and engineering. The research plan, inspired by the unique properties of topological robustness discovered in quantum systems, envisions topological acoustic waves that can be engineered in artificial acoustic lattices and synthetic elastic media, and that are immune to unwanted scattering and back-reflection caused by imperfections in device fabrication or impedance mismatch. The approaches to topological order for sound and mechanical waves exploit two advanced concepts based on synthetic gauge fields. The first approach relies on breaking time-reversal symmetry by applying an angular momentum bias based on mechanical or spatio-temporal modulation, emulating the effect of a dc magnetic field. The second approach relies on the principle of synthetic spin-orbital coupling, acting on a pseudo-spin engineered in mechanical systems with preserved time-reversal symmetry. Building upon these two mechanisms, the engineering of acoustic systems and devices with one-way and helical edge transport is advanced. Thanks to the inherent robustness against local defects and disorder, a variety of novel devices with topological protection will be engineered to steer sound and mechanical waves along arbitrary pathways in two and three dimensions, leading to increased bandwidth, multiplexing, reconfigurability and novel architectures for acoustic systems.

传播，干扰和散射是声学和其他机械波的波性质的基本表现。几个世纪以来，人类一直在一定程度上使用这些特性来控制和操纵声音，例如实现乐器，音乐厅和耳语画廊。但是，最近在冷凝物质物理学中发现了基于先进拓扑概念的物质组织的新原则。这些概念的动机是在物理和工程分支机构工作的科学家。通过在适当设计的复合材料系统的分散中利用拓扑约束，可以实现高度非局部反应，并在其波传播特性中具有异常稳定性。该项目的目的是将这些概念转化为声学和机械系统。目标是重新定义对波浪现象的理解，并显着扩大操纵机械和声波的能力。这项研究的结果将扩大工程工具包，改善机械和声学设备的体系结构，例如，通过减少包括换能器，接收器和共振元素在内的不同组件之间的不良相互作用。这种方法将通过拓扑保护赋予机械波的传播，从而在没有反射的情况下沿任意形状的途径进行单向引导，并使缺陷和混乱使其稳健。由于该项目桥接了几个学科，包括材料科学，物理和工程学，因此其多学科特征将产生积极的教育影响。该项目将扩大背景并改善参与该项目的学生的准备，并且由于与多样化的学科的广泛重叠，包括音乐和声音的工程，它将扩大代表性不足的少数群体在研究和教育中的参与。将拓扑秩序的概念应用于拓扑和机械浪潮的概念，并在科学领域的众多科学领域，从而在科学领域中开辟了众多的机械场所。该研究计划的灵感来自量子系统中发现的拓扑鲁棒性的独特性能，它设想了可以在人工声学晶格和合成弹性介质中设计的拓扑声波，并且可以免受不必要的散射以及由设备制造或阻碍摩擦式的不完善的散射和背部反射。拓扑顺序的声学顺序和机械波利用了基于合成量规场的两个高级概念。第一种方法依赖于基于机械或时空调制的角动量偏置来打破时间反转对称性，从而模拟了直流磁场的效果。第二种方法取决于合成旋转轨道耦合的原理，该原理作用于具有保留时间反转对称性的机械系统中的伪旋转。在这两种机制的基础上，具有单向和螺旋边缘传输的声学系统和设备的工程。得益于对局部缺陷和混乱的固有稳健性，各种具有拓扑保护的新型设备将被设计为在两个和三个维度的任意途径沿任意途径的声音和机械波，从而导致带宽，多发性，可重复性和新颖的声学体系结构。