Collaborative Research: Nonlinear Coupling and Relaxation Mechanisms in Micro-mechanics

微型机电系统处于现代技术的前沿。它们的体积和质量都很小，可以实现各种类型的控制。许多消费、工业和军事设备依靠这些系统进行传感和信号调节。速度、精度、稳定性和可靠性是其性能的重要特征。振动是许多微机电系统运行的核心。该项目涉及对这些系统振动的基础研究，目的是确定哪些特性限制了它们的性能，以及如何改进这些性能。利用理论和实验工具开发这些振动的物理模型，将提供关键的理解，从而允许新的操作模式和增强的能力。而且，虽然该项目的实验方面将集中在微机电系统上，但所开发的振动和噪声模型将是通用的，并适用于光学系统，甚至更小的纳米级机械设备，为纳米技术的进一步发展铺平道路。该项目更广泛的影响包括拓展、指导和培训本科生和研究生，纳入代表性不足的群体的学生，开发受研究激励的课堂材料，以及传播结果。该项目将为四所大学的学生提供多学科培训，他们将受益于分析、计算和实验相结合的研究经验。由于其体积小，微机电振动系统本质上是有噪声的。小尺寸的另一个后果是，获得足够强的信号需要在振动幅值很大的情况下工作，使振动成为非线性。非线性和噪声的相互作用导致了新的现象，为了避免它们，或者在应用中利用它们，必须了解这些现象。在这种情况下，非线性共振现象特别有趣，丰富，具有智力挑战性，并且有望在微尺度器件中实现。在存在衰减和噪声的情况下，共振非线性模态的行为，以及噪声、衰减和非线性的基本微观机制尚不清楚。也不知道如何检测和表征非线性系统中的波动，因为它们以一种非平凡的方式被非线性干扰。这项工作将在理论上和实验中解决这些问题。它还将开发利用光学和静电方法进行实验控制和表征谐振模式的新技术。主要研究人员已经建立了合作记录，这将加强理论和实验工作之间的紧密联系。

Micro-scale electro-mechanical-systems are at the cutting edge of modern technology. They have small size and mass and allow the implementation of various types of control. Many consumer, industrial, and military devices rely on these systems for sensing and signal conditioning. Speed, precision, stability, and reliability are important characteristics of their performance. Vibrations are at the core of the operation of many of these micro-electro-mechanical systems. This project involves a fundamental study of the vibrations of these systems, with the goal to establish what properties limit their performance and how this performance can be improved. The development of physics-based models for these vibrations, using both theoretical and experimental tools, will provide key understanding that will allow for new modes of operation and enhanced capabilities. And, while the experimental aspects of the project will focus on micro-electro-mechanical systems, the vibration and noise models developed will be general and applicable to optical systems and to even smaller mechanical devices that operate at the nanoscale, paving the way for further progress in nanotechnology. The broader impacts of the project include outreach, mentoring and training of undergraduate and graduate students, inclusion of students from underrepresented groups, development of classroom materials motivated by the research, and dissemination of results. The project will result in multidisciplinary training of students at four universities who will benefit from the combined analytical, computational, and experimental research experiences.Because of their small size, micro-electro-mechanical vibrational systems are intrinsically noisy. Another consequence of the small size is that obtaining a sufficiently strong signal requires operating in a regime where the vibration amplitudes are large, making the vibrations nonlinear. The interplay of nonlinearity and noise leads to new phenomena, and these must be understood in order to avoid them, or to utilize them in applications. In this context, nonlinear resonant phenomena are particularly interesting, rich, intellectually challenging, and promising for implementation in micro-scale devices. The behavior of resonating nonlinear modes in the presence of decay and noise, as well as the fundamental microscopic mechanisms of noise, decay, and nonlinearity are poorly understood. Nor is it understood how to detect and characterize fluctuations in nonlinear systems, as they are intervened with the nonlinearity in a nontrivial way. The work will address these issues both theoretically and in experiments. It will also develop new techniques for experimental control and characterization of resonating modes using optical and electrostatic methods. The principal investigators have an established record of collaboration, which will strengthen a close connection between the theoretical and experimental work.