CAREER: Acoustic Phonons in 2D Materials

非技术描述该项目研究声波如何使用基于激光的技术在一类新的原子薄二维（2D）材料中移动，如何使用化学改变这种运动，以及如何使用这些知识来增强技术。声波在固体材料中以“声子”的形式运动，声子的作用就像声音的单个粒子。声子可以携带热量并影响携带电流的电子，从而影响材料设备和应用。该项目将进一步了解二维材料的声子性质，填补我们基础知识的主要空白。这项工作培养本科生和研究生的职业生涯在科学和工程。教育和更广泛的外联目标包括：（i）开发一个公开的在线布里渊光谱数据库，（ii）每年举办一次为期一天的Sciimpact-East会议，向普罗维登斯、RI地区服务不足的高中学生和教师介绍科学和技术职业，及（iii）招聘以下人士─代表少数民族和女性高中生和本科生参与科学研究。技术说明该奖项支持一个项目，以了解二维（2D）硫族化物（S，Se，Te）和氧化物材料的声子性质，以匹配我们目前对其电子性质的理解。布里渊激光散射将用于绘制内部合成的2D材料的声学声子色散关系。新的插层化学将被引入到系统地控制层间声子的行为，通过化学调制层间耦合。缺陷（空隙，空位和晶界）将使用化学方法设计成2D材料，以研究它们对基本声子行为的影响。这项工作奠定了基础，在2D硫属化物和氧化物材料的声子的完整的理解和化学控制，并将指导理解的机械行为，热传输和设备故障在未来的应用2D材料。

Non-Technical Description This project studies how sound waves move in a new class of atomically-thin, two-dimensional (2D) materials using a laser-based technique, how to alter this motion using chemistry, and how to use this knowledge to enhance technologies. Sound waves in solid materials move in the form of "phonons," which act like individual particles of sound. Phonons can carry heat and affect electrons that carry electrical currents, impacting material devices and application. This project will further the understanding of the phonon properties of 2D materials, filling a major gap in our fundamental knowledge. This work trains undergraduate and graduate students for careers in science and engineering. Educational and broader outreach goals include: (i) development of a publicly available online Brillouin spectroscopy database, (ii) initiation of an annual one-day Sciimpact-East conference to introduce underserved high school students and teachers in the Providence, RI area to careers in science and technology, and (iii) recruitment of under-represented minority and female high school students and undergraduates to participate in scientific research.Technical Description This award supports a project to understand the phononic properties of two-dimensional (2D) chalcogenide (S, Se, Te) and oxide materials to match our current understanding of their electronic properties. Brillouin laser light scattering will be used to map the acoustic phonon dispersion relations of 2D materials, synthesized in-house. Novel intercalation chemistries will be introduced toward systematically controlling the interlayer phonon behavior by chemically modulating the layer-to-layer coupling. Defects (voids, vacancies, and grain boundaries) will be engineered into 2D materials using chemical methods for investigating their impact on fundamental phonon behavior. This effort lays the foundation for the complete understanding and the chemical control of phonons in 2D chalcogenide and oxide materials and will guide understanding of mechanical behavior, heat transport and device failure in future applications of 2D materials.