CAREER: Towards Control of Photo-Induced Charges in Chiral Nanocomposites via Optical Spin-Orbit Interactions

技术：该职业奖的研究部分旨在了解手性纳米复合材料中的光致电能流动，在前所未有的低光强度（1 W/cm^2）下，由于明显的光致磁场和纳米颗粒之间的相互作用，可以观察到非线性光学现象。这些与光学自旋-轨道相互作用有关的效应，在理论上被低估了，也没有得到很好的理解；改进数值模型，使它们能够正确估计测量的强度依赖和极化依赖过程是本项目的优先事项。部分金属包覆的电介质纳米球样品被包含在透明导电聚合物中，并通过电泳和外部磁场处理技术组装。散射、瞬态吸收、电场和磁场测量表征了改性纳米颗粒的排列和发生在周围导电聚合物中的低频电荷输运。非技术：该项目涉及与技术相关的材料科学主题领域的基础研究问题。纳米复合材料为新的光电子学、太阳能收集和光催化应用提供了一个平台。该项目的教育活动旨在吸引、培养和留住各种背景的富有创造力、足智多谋的学生，特别强调那些在纽约皇后区和布朗克斯区外的公立学校就读的学生。为积极上进的大学预科学生、专业硕士生和国际合作者提供研究机会，解决博士课程之前和之外的科学训练需求。

Technical: The research component of this CAREER award aims to understand the photo-induced electrical energy flows in chiral nanocomposite materials where nonlinear optical phenomena are observed at unprecedented low light intensities (1 W/cm^2) stemming from the appreciable photo-induced magnetic fields and the interactions between nanoparticles. These effects, associated with optical spin-orbit interactions, are theoretically underestimated and not well understood; refining numerical models so that they properly estimate the measured intensity-dependent and polarization-dependent processes is a priority in this project. Samples of partially-metal-coated dielectric nanospheres are subsumed in transparent conducting polymers and assembled electrophoretically and with external magnetic-field processing techniques. Scattering, transient absorption, electrical, and magnetic field measurements characterize the modified nanoparticle alignment and the low-frequency charge transport that occurs in the surrounding conducting polymer.Non-technical: The project addresses basic research issues in a topical area of materials science with technological relevancy. Nanocomposite materials provide a platform for new optoelectronics, solar harvesting, and photocatalysis applications. The educational activities of this project are designed to attract, train, and retain creative, resourceful students of all backgrounds, with special emphasis on those attending public schools in the outer New York boroughs of Queens and the Bronx. Research opportunities for highly motivated pre-college students, professional Master's students, and international collaborators address the need for scientific training prior to and outside of a doctoral program.