FRG: A Mechanical Signature of the Polarization of Light: The Opto-Mechanical Effect in Glass

先进光子学的许多应用需要将光信号转换为机械信号。目前，这种信号转换仅通过中间使用适当的电子设备来完成，成本很高，信号质量也会降低。最近关于硫化物(AsSe)玻璃薄膜中的光机械效应(OME)的报道预测，有可能将光学信息忠实地转换为机械信号，而不需要电子设备的干预。OME还展示了在纳米驱动器、纳米传感器、纳米开关等纳米器件中的潜在应用。显然，OME的发现有可能开启材料科学的一个新领域，并对技术产生重大影响。然而，目前甚至连OME的定义参数和基本起源都不清楚。它们是这项重点研究小组(FRG)提案的主题。它建立在不到一年前NSF与发现这种效应的剑桥小组合作，为利哈伊的实验提供的一小笔探索性研究拨款(SGER)的初步成功的基础上。通过该项目，将理论模拟与光诱导玻璃电子和物理结构变化的实验观察相结合，并直接观察到各种参数的影响，从而获得对OME的原子学理解。将研究三个模型硫化物玻璃系统，目的是利用新的数据来开发更强的效果和更快的动力学更好的成分。OME是一种矢量光学现象(取决于E矢量)，它叠加在标量光诱导的玻璃结构变化上。使用一种临时设置，PI将通过来自同步加速器的偏振X射线来确定前者的微观起源。当然，对标量效应的理解将是一个有价值的副产品，这将有助于阐明类似玻璃中的各种其他光诱导现象，如光变暗、光膨胀、光熔化、光塑性、光结晶等。本项目将研究玻璃中一种新发现的现象--光技术效应。这一新现象有可能从根本上提高电信质量。此外，它在极小的设备中也有潜在的应用。该项目结合了两个实验小组(英国利哈伊大学的H.Jain和英国剑桥大学的S.R.Elliott)和一个理论小组(俄亥俄大学的D.A.Drabold)作为首席调查人员的互补专业知识。它还将为几名学生和博士后提供一个将实验与理论相结合的国际跨学科材料研究的不同寻常的机会。学生会定期在三位督导员的督导下会面和交换学位，并进行工作。这个重点研究小组的项目由材料研究部的陶瓷项目和数学和物理科学局的多学科活动办公室共同资助。*

Numerous applications of advanced photonics require conversion of an optical signal to mechanical signal. Currently such signal transformation is accomplished only with the intermediate use of appropriate electronics at a significant cost and loss of signal quality. The recent report of the opto-mechanical effect (OME) in a chalcogenide (AsSe) glass film predicts the possibility of faithfully transforming optical information into mechanical signal, bypassing the intervention of electronics. The OME also shows potential use in nano-devices such as nano- actuators, nano-sensors, nano-switches etc. Clearly, the discovery of OME has potential of starting a new area of materials science and make significant impact on technology. However, at present even the defining parameters and the fundamental origin of OME are not known. They are the subject of this Focused Research Group (FRG) proposal. It is built on the initial success of a Small Grant for Exploratory Research (SGER) provided by NSF less than a year ago for experiments at Lehigh, in collaboration with the Cambridge group that discovered the effect. From the project, an atomistic understanding of OME by combining theoretical simulations with the experimental observations of light-induced changes in the electronic and physical structures of glass, and the direct observations of the effect as a function of various parameters will be obtained. Three model chalcogenide glass systems will be studied, with the intent of using the new data for developing superior compositions with stronger effect and faster kinetics. The OME is a vector optical phenomenon (depending on the E vector), which is superimposed on scalar light-induced changes in the structure of glass. Using an improvised setup, the PIs will establish the microscopic origin of the former by polarized x-rays from a synchrotron. Naturally the understanding of scalar effects will be a valuable byproduct, which will help clarify various other light-induced phenomena in similar glasses, such as photo-darkening, photo-expansion, photo-melting, photo-plasticity, photo-crystallization, etc. This project will study a newly discovered phenomenon, the optomechnical effect, in glasses. This new phenomenon has potential to radically improve the quality of telecommunications. In addition, it has potential applications in extremely small devices. The project combines complementary expertise of two experimental groups (H. Jain at Lehigh University and S.R. Elliott at Cambridge University in the United Kingdom) and one theory group (D.A. Drabold at Ohio University) as Principal Investigators. It will also provide to several students and postdocs an unusual opportunity for international, interdisciplinary materials research integrating experiments with theory. The students will periodically meet and exchange places and conduct work under the supervision of the three PIs. This Focussed Research Group project is co-funded by the Ceramics Program in the Division of Materials Research and the Office of Multidisciplinary Activities in the Directorate for Mathematical and Physical Sciences.***