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，这种信号转换只能通过中间使用适当的电子设备来完成，而且成本很高，信号质量也会下降。最近关于硫族化物（AsSe）玻璃薄膜的光机械效应（OME）的报道预测了将光信息忠实地转换为机械信号的可能性，绕过了电子的干预。该材料还显示出在纳米器件如纳米致动器、纳米传感器、纳米开关等方面的潜在用途。显然，OME的发现有可能开创材料科学的新领域，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知道。他们是本重点研究小组（FRG）提案的主题。它建立在不到一年前由国家科学基金会提供的探索性研究小额赠款（SGER）的初步成功的基础上，该赠款是与发现该效应的剑桥小组合作在里海进行的实验。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，对OME的原子性理解，以及作为各种参数函数的效应的直接观察。将研究三种模型硫系玻璃体系，目的是利用新数据开发具有更强效果和更快动力学的优越组合物。OME是一种矢量光学现象（取决于E矢量），它叠加在玻璃结构的标量光诱导变化上。使用临时装置，pi将通过同步加速器的偏振x射线来确定前者的微观起源。自然，对标量效应的理解将是一个有价值的副产品，它将有助于澄清类似玻璃中的各种其他光致现象，如光变暗、光膨胀、光熔融、光塑性、光结晶等。这个项目将研究一种新发现的现象，即眼镜的光学效应。这种新现象有可能从根本上提高电信的质量。此外，它在非常小的设备中也有潜在的应用。该项目结合了两个实验组（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）作为主要研究人员的互补专业知识。它还将为一些学生和博士后提供一个不寻常的机会，进行国际跨学科材料研究，将实验与理论相结合。学生将在三位pi的监督下定期会面和交换位置并开展工作。该重点研究小组项目由材料研究部陶瓷项目和数学与物理科学理事会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.***