Metamaterial Design Platform and Dynamic Building Blocks for Non-Equilibrium, Symmetry-Violating Manipulation of Mechanical Waves

这笔资金将用于研究如何处理存储在声波和机械振动中的信息，并将其应用于声纳、医用超声波和结构诊断技术，从而促进科学进步，促进国家繁荣和健康，保障国防安全。20世纪可编程微电子电路的发展使电信号的快速、精确和按需操作成为可能，从而开启了信息时代。目前还不存在处理机械信息的类似技术。它们需要设计微型声学电路元件，这些元件可以以大阵列的形式链接在一起，并单独编程。该项目将通过研究操纵原子薄微机械元件的振动特性的方法，以及开发新的数学和计算技术来预测它们的集体行为，从而在可编程声学微芯片方面取得关键进展。这些活动将被纳入大学预科暑期课程和本科生研究体验，旨在提高STEM的保留率，促进目前代表性不足群体的个人参与。本研究旨在创建一类新的可单独寻址和可重新配置的微机械积木，并推导出一个数学模型，以可预测地操纵此类积木的耦合组件中的振动，从而实现基本的声音处理能力：放大、整流、二进制信息存储和逻辑运算。构建块和互连将由石墨烯纳米机电薄膜谐振器组成，其独特的物理特性使其能够使用静电场或光场来局部调制弹性和耦合，速度和强度前所未有。并行的理论工作将结合有限元模拟和离散Floquet分析来建模具有时间调制参数、时空周期性和非线性响应的机械系统。这些进展将通过与未来声学技术相关的非平衡声学功能的实验演示来展示，如相干放大、相位同步、数字信息处理、PT过渡边缘检测以及与未来声学技术相关的空间和时间尺度上的单向声音传输。除了推进声学电路和活性材料的工程设计，这项工作还为测试现代物理和材料科学中的基本概念提供了实验基础，如宇称时间对称破缺、非厄米特拓扑保护和基于谐振器的神经形态计算。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This grant will fund research that enables manipulating information stored in sound waves and mechanical vibrations, with application to sonar, medical ultrasonic, and structural diagnostic technologies, thereby promoting the progress of science, advancing the national prosperity and health, and securing the national defense. The development of programmable microelectronic circuits in the 20th century ushered in the information age by enabling fast, precise, and on-demand manipulation of electrical signals. Similar technologies for manipulating mechanical information do not yet exist. They require devising microscale acoustic circuit elements that can be chained together in large arrays and individually programmed. This project will make critical advances toward programmable acoustic microchips by investigating methods to manipulate the vibrational properties of atomically thin micromechanical elements, as well as developing new mathematical and computational techniques to predict their collective behavior. These activities will be incorporated into pre-collegiate summer programs and undergraduate research experiences, which are tailored to improve retention in STEM and boost participation of individuals from currently underrepresented groups.This research aims to create a new class of individually addressable and reconfigurable micromechanical building blocks, as well as to derive a mathematical model to predictably manipulate vibrations in coupled assemblies of such building blocks, thereby realizing essential sound manipulation capabilities: amplification, rectification, binary information storage, and logic operations. The building blocks and interconnects will consist of graphene nanoelectromechanical membrane resonators, whose unique physical properties enable the use of electrostatic or optical fields to locally modulate elasticity and coupling with unprecedented speed and strength. The parallel theoretical effort will combine finite-element simulations with discrete Floquet analysis to model mechanical systems with time-modulated parameters, space-time periodicity, and nonlinear response. These advances will be showcased through experimental demonstrations of nonequilibrium acoustic functionalities, such as coherent amplification, phase-synchronization, digital information processing, PT-transition-edge sensing, and one-way sound transmission at spatial and temporal scales relevant to future acoustic technologies. Beyond advancing the engineering design of acoustic circuits and active materials, the work provides an experimental foundation for testing fundamental concepts in modern physics and materials science, such as parity-time symmetry breaking, non-Hermitian topological protection, and resonator-based neuromorphic computing.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.