EAGER: Ultra-High Frequency Phononic Devices

通过理论和实验评估表明，表面声波通过工程“声子”晶格传播会产生令人兴奋的新特性，包括“通过”和“停止”频带、分数波长传播、模式跳变和高频共振。表面声波通过这些晶格传播的理论和实验研究可以通过这些工程结构的单元格的大小和几何形状来控制。然而，大多数工作都局限于兆赫范围内的中等频率。从根本上说，这些结构可以通过缩小和设计达到超高频范围。本EAGER项目提出通过开发一种新型纳米结构声子晶格器件并探索其特性来研究将这种表面声波结构的工作频率提高到超高频的问题。此外，提出了一种新的完全集成的表面声波-声子晶格器件，该器件具有提供独特声波逻辑功能的潜力。这项研究的潜在好处可能会在电子工业中产生变革，因为可以开发出一种新的声波器件家族，在超高频和数字开关领域具有独特的性能，具有许多关键应用，例如分数波长超透镜成像，用于安全通信的超高频声学共振滤波器，开关声子逻辑元件，超灵敏传感等。对这些结构的基本理解将大大推动声波传播和产生领域的发展，并将允许将此类研究纳入大多数电子教科书中，这将有利于学生的发展。在社会需求方面，预计它将通过超高频安全通信、声学逻辑元件、机场安全的超透镜声成像、超高灵敏度传感器等应用产生巨大影响，这些应用对家庭、医院、机构、机场、学校和车辆安全的社会需求至关重要。该项目的目标是探索和开发一种基于具有不同单元尺寸和几何形状的自组装纳米结构薄膜的声子晶格的新型超高频声学纳米器件。本项目将引入并采用三种关键的创新方法(a)开发用于声子晶格的压电纳米结构的自组装及其基本声波特性的研究，(b)开发和研究用于纳米结构声子晶格的表面声波输入和输出，以及(c)将纳米声子晶格与主动声波逻辑元件的输入和输出集成。该项目将设计千兆赫范围内的基频，并研究通过分数波长上转换和缩小到亚太赫兹范围。提出了一种开发新型声学纳米器件的新方法，将从理论上和实验上探索纳米声子晶格的特性，探索频率上转换，模式跳变到更高频率的光学分支，以及通过声子晶格进行超高频应用的高阶共振。提出的研究重点是介绍和探索声子器件开发中的新概念，以实现超高频性能和独特的主动开关功能，这对集成声学器件和电路具有潜在的变革性影响。

Surface acoustic wave propagation through engineered "phononic" crystal lattices was shown by theoretical and experimental evaluations to result in exciting new properties with "pass" and "stop" frequency bands, fractional wavelength propagation, mode hopping and high frequency resonances. The theoretical and experimental research on the propagation of surface acoustic waves through these lattices can be controlled by the size and geometry of the unit cell of these engineered structures. Yet, most of the work has been limited to moderate frequencies at megahertz ranges. Fundamentally, these structures can reach ultra-high frequency ranges through scaling down and design. This EAGER project proposes to study the problem of increasing the frequency of operation to ultra-high frequencies of such surface acoustic wave structures by developing a novel nanostructured phononic lattice device and exploring its properties. Furthermore, a novel fully integrated surface acoustic wave-phononic lattice device is proposed that has the potential to provide unique acoustic wave logic functions. The potential benefits of this research can be transformational in the electronics industry as a new family of acoustic wave devices can be developed with unique properties in the ultra-high frequency, and digital switching domain, with a host of key applications, such as superlensing imaging at fractional wavelengths, ultra-high frequency acoustic resonance filters for secure communications, switching phononic logic elements, ultra-sensitive sensing and others. The fundamental understanding of these structures will advance substantially the field of acoustic wave propagation and generation and will allow incorporation of such research in most electronics text books that will benefit student development. In societal needs it is anticipated to have a tremendous impact through applications in ultra-high frequency secure communications, acoustic logic elements, superlensing acoustic imaging for airport security, ultra-high sensitivity sensors, that are critical to societal needs for home, hospitals, institutions, airports, schools and vehicle safety. The goal of the project is to explore and develop a novel family of ultra-high frequency acoustic nanodevices based on phononic lattices of self-assembeled nanostructured thin films with different unit cell size and geometry. Three key innovative approaches will be introduced and employed for this project (a) the development of the self-assembly of piezoelectric nanostructures for the phononic lattice with the study of its fundamental acoustic wave properties, (b) the development and study of the surface acoustic wave inputs and outputs for the nanostructured phononic lattice, and (c) the integration of the nano-phononic lattice with inputs and outputs for an active acoustic wave logic element. The project will design for fundamental frequencies f0 in the gigahertz range and and study upconversion through fractional wavelength and scaling-down to sub-terahertz ranges. The proposed novel approach to developing a new family of acoustic nanodevices will explore the properties of the nano-phononic lattices theoretically and experimentally, explore frequency upconversion, mode hopping to higher frequency optical branches, and higher order resonances through the phononic lattice for ultra-high frequency applications.The proposed research focuses on introducing and exploring new concepts in phononic device development for ultra high frequency performance and unique capabilities for active switching that has a potentially transformative impact on integrated acoustic devices and circuits.