Acoustic Resonances in Solids: Pressure-, Spatial- and Photo-tuning

凝聚态物理项目将开发一种新的激光光散射技术，以测量材料的弹性常数，最高可达兆巴压力，可在钻石顶压室中实现。这项研究是基于对由于表面波纹效应而产生的驻波共振的检测。这项技术对不透明材料的研究特别有用，并将应用于地球物理中重要的关键材料。提出的实验应该提供对与埋藏的界面和嵌入的层流结构相关的鲜为人知的变形机制和弹性特性的物理学方面的见解。声波在这些系统中的频率分布和空间限制将为声波器件的应用提供新的机会。此外，还将研究在二元硫化物玻璃中稳定在最佳连接性的一种新的光改性玻璃状态的不寻常的机械性能。同样令人感兴趣的是机械稳定性和明显的玻璃形成倾向之间的重要相互作用，这些倾向与原子之间的局部连接性有关。该项目将培训研究生和本科生在当代固体物理学中提出具有挑战性的问题。他们将在现代激光光谱技术方面获得宝贵的经验。这一教育将为他们在学术界或工业中从事富有成效的职业生涯做好准备。该项目将支持对固体声学和机械性质的激光光谱学研究。这项研究涉及材料在极端压缩-接近地球内部压力-的情况下的行为。这将开发一种新的方法来探索材料的高压行为，并将为材料结构性能理论提供关键参数。对局限于埋藏层的高频声波的研究将为局域激发的物理学提供重要信息。波的频率分布和空间限制将产生新的技术机会，而不会受到传统表面波设备带宽限制的影响。拟议中的玻璃研究通过创造一种新的、光修饰的状态来解决其弹性和光学特性的关键方面。感兴趣的是这种状态的性质如何与玻璃的形成有关，以及玻璃的性质如何取决于原子的特定局部连接性。再加上玻璃的非晶性带来的自由和弹性，这种不同寻常的光诱导效应可能会在这些有用的材料中产生具有技术价值的结果。这项研究将在研究生和本科生的帮助下进行。他们将通过参与固体物理和激光光谱学技术的当代前沿研究，获得宝贵的经验。这些经验将对他们的进一步学习或在工业界、学术界或政府实验室就业具有重要价值。

The condensed matter physics project will develop a new laser light scattering technique to measure the elastic constants of materials up to mega-bar pressures achievable in a diamond anvil cell. The research is based on the detection of standing wave resonances that develop because of surface corrugation effects. The technique is particularly useful for studies of opaque materials and will be applied to key materials important in geophysics. Experiments are proposed that should provide insights into the physics of poorly understood deformation mechanisms and elastic properties associated with buried interfaces and embedded laminar structures. The frequency profile and spatial confinement of acoustic waves confined in these systems will yield new opportunities for acoustic wave device applications. In addition, the unusual mechanical properties of a new, photo-modified, state of glass that is stabilized at optimum connectivity in binary chalcogenide glasses will be investigated. Also of interest is the important interplay between mechanical stability and pronounced glass forming tendencies related to local connectivity between atoms. The project will train graduate and undergraduate students in challenging issues in contemporary solid state physics. They will gain valuable experience with modern laser spectroscopy techniques. This education will prepare them for productive careers in academia or industry.The project will support a laser spectroscopy study of the acoustic and mechanical properties of solids. The research involves the behavior of materials under extreme compression - approaching pressures at the Earth's interior. It will develop a new method to probe high-pressure behavior of materials and will yield critical parameters for theories of material structural properties. The study dealing with high frequency acoustic waves confined to buried layers should provide important information into the physics of localized excitations. The frequency profile and spatial confinement of the waves will yield new technological opportunities that will not suffer from bandwidth limitations of conventional surface wave devices. The proposed study of glasses addresses key aspects of their elastic and optical properties through creation of a new, photo-modified, state. Of interest is how the properties of this state relate to the formation of glasses and how glass properties depend on the specific local connectivity of atoms. Together with the freedom and flexibility associated with the non-crystalline nature of glasses, the unusual light-induced effects may yield results of technological value in these useful materials. This research will be conducted with the aid of graduate and undergraduate students. They will gain valuable experience through their involvement in contemporary forefront research in solid state physics and laser spectroscopy techniques. These experiences will be of great value in their further studies, or employment in industry, academia or government laboratories.