CAREER: Optical Spectroscopy of the Soft-Modes in Multiferroic Single Crystals

职业：多铁性单晶中软模式的光谱学

• 批准号: 0546985
• 负责人: Andrei Sirenko
• 金额: $ 49.65万
• 依托单位: New Jersey Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2011-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0546985&HistoricalAwards=false
• 关键词: CAREER; Optical; Spectroscopy; Soft; Modes

*****NON-TECHNICAL ABSTRACT*****This Faculty Early Career Award at New Jersey Institute of Technology (NJIT) focuses on integrating fundamental studies of multiferroics with the education of students at different levels. Multiferroics belong to a novel class of oxide materials, whose magnetic and electrical properties are interconnected and can influence each other at low temperatures. Recently these materials have attracted great interest within the condensed-matter community and beyond due to the recognized potentials of multiferroics for future multifunctional device applications including magnetically recorded computer memory, optical switches for communication, and mechanical actuators. A comprehensive theory of the mechanisms for multiferroic effects is still under development. The proposed experimental studies of the related atomic vibrations will contribute to an increased understanding of these effects. The studies will also help in the search for new multiferroics that may lead to future devices that can operate in weaker magnetic fields and at higher temperatures. A diverse curriculum will be developed to promote the integration of modern materials research and education. Several Physics courses at NJIT, e.g. "Fundamental of Spectroscopy" and "Advanced Physics Laboratory", are to be directly associated with the proposed research. A comprehensive online course of Introductory Physics will be created for freshman students and will be used in outreach programs to local high-school students.*****TECHNICAL ABSTRACT*****This Faculty Early Career Award at New Jersey Institute of Technology (NJIT) focuses on the integration of fundamental optical spectroscopy of the soft modes in multiferroic materials with education of students at different levels. Multiferroic magnetoelectrics belong to a novel class of ferroic oxides, whose magnetization and electrical polarization are closely coupled and can influence each other. By applying an electric field one can change the magnetization M in these crystals, while an external magnetic field affects the polarization P. A theoretical understanding of the P-M coupling at the crystal lattice level does not currently exist. The proposed experiments will use far-infrared spectroscopy at the National Synchrotron Light Source and Raman scattering, both in a magnetic field, to focus on this issue. The major research goal is to relate the interplay between anomalies in the dielectric function and magnetization of multiferroic single crystals to the behavior of the soft mode phonons, magnons, and crystal-field infrared-active excitations. Collaboration with National synchrotron radiation facilities is a key part of this project. Several Physics courses will be directly associated with the proposed research: "Fundamental of Spectroscopy" for graduate students and "Advanced Physics Laboratory" for fourth-year undergraduates. A comprehensive online course of Introductory Physics as well as a web-based interactive tool "Prepare for the Coming Quiz" will be created for freshman students and will be used in outreach programs to local high-school students.

*****非技术摘要*****新泽西理工学院（NJIT）的该教师早期职业奖的重点是将多效中学的基本研究与对不同级别的学生的教育相结合。多表象属于一种新型的氧化物材料，其磁性和电性能是相互联系的，并且可以在低温下相互影响。最近，由于多表演器对未来的多功能设备应用的公认潜力，包括磁性记录的计算机存储器，通信的光学开关和机械执行器，这些材料引起了浓缩型社区及其他地区的极大兴趣。关于多效效应机制的综合理论仍在开发中。相关原子振动的拟议实验研究将有助于增加对这些影响的理解。这些研究还将有助于寻找新的多表演器，这些多效应可能导致未来的设备，这些设备可能在较弱的磁场和较高温度下运行。将开发多种课程，以促进现代材料研究和教育的整合。 NJIT的几个物理课程，例如“光谱法的基础”和“先进的物理实验室”应与拟议的研究直接相关。将为新生学生创建一个全面的在线入门物理学课程，并将用于当地高中生的外展计划。*****技术摘要*****新泽西技术学院（NJIT）的这项早期职业奖（NJIT）重点介绍了与不同程度教育的多型材料中软模式的基本光谱的整合。多种磁电磁性属于一类新型的铁氧化物，其磁化和电化极化是紧密耦合的，可以相互影响。通过施加电场，可以在这些晶体中改变磁化强度，而外部磁场会影响极化P。当前不存在对晶体晶格水平的P-M偶联的理论理解。所提出的实验将在磁场中的国家同步子光源和拉曼散射上使用远红外光谱，以关注这个问题。主要的研究目标是将介电函数中异常和多种表色单晶磁化的相互作用与软模式声子，镁和晶体场红外红外激活激发的行为联系起来。与国家同步辐射设施的合作是该项目的关键部分。几个物理课程将直接与拟议的研究直接相关：研究生的“光谱学的基础”和四年级大学生的“高级物理实验室”。全面的在线入门物理学以及基于网络的交互式工具“准备即将到来的测验”将为新生学生创建，并将用于当地高中生的外展计划。