Emergent Collective Phenomena in Transition Metal Oxides

****技术摘要****该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。复杂的氧化物为研究电子之间强相互作用产生的新型电子、磁性和结构现象提供了许多机会，例如高Tc超导电性、量子自旋液态和磁电。了解它们潜在的微观机制以及探索它们丰富的相图对凝聚态物理提出了巨大的挑战。这个个人研究者奖支持一个研究几个典型过渡金属氧化物的项目，以解决一些基本问题，特别是关注如何相关的自由度，如自旋、电荷和晶格，是如何耦合的，以诱导上述复杂的性质。特别感兴趣的是探索量子磁体和受挫磁体中可能的新相和量子相变，检查高Tc超导体中的电子-声子耦合，以及测试磁多铁性中相互矛盾的理论模型。将采用弹性/非弹性中子散射技术直接探测固体在原子长度尺度上的静态和动态特性。本科生和研究生将在美国、欧洲和日本的几个国际顶级研究机构进行晶体生长和中子散射测量。****非技术摘要****该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。电子是一种携带电荷和自旋（磁矩）的基本粒子。在固体中，电子丰富，当满足一定条件时，电子可以相互强烈地相互作用，产生新的现象。强相关电子系统中集体行为的著名例子是超导性，它导致磁悬浮和多铁性，允许人们同时控制磁性和电子性质，这两者都具有潜在的革命性工业应用。本项目将通过研究几种典型的复合氧化物来解决这些现象的关键问题。这一结果将促进我们对自旋、电荷和晶格如何相互关联导致这种效应的理解。这项研究将为如何更好地设计未来技术应用的特性提供重要信息。本科生和研究生将在多个国际顶级研究机构接受最先进的晶体生长和表征技术的培训，并有机会发展自己的国际研究网络。

****TECHNICAL ABSTRACT****This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Complex oxides provide numerous opportunities to study novel electronic, magnetic, and struc-tural phenomena that emerge out of strong interactions between electrons, such as high Tc su-perconductivity, quantum spin liquid states, and magneto-electricity. Understanding their under-lying microscopic mechanisms as well as exploring their rich phase diagrams poses grand challenges in condensed matter physics. This individual investigator award supports a project to study several exemplary transition metal oxides to address some fundamental questions, especially focusing on how the relevant degrees of freedom, such as spin, charge, and lattice, are coupled to induce the aforementioned complex properties. Of particular interest are the exploration of possible new phases and quantum phase transitions in quantum and frustrated magnets, examination of electron-phonon coupling in high Tc superconductors, and testing conflicting theoretical models in magnetic multiferroics. Elastic/inelastic neutron scattering techniques that directly probe static and dynamic properties of solid at the atomic length scale will be employed. Undergraduate and graduate students will spend time at several internationally top research institutes in the U.S., Europe, and Japan for crystal growth and neutron scattering measurements.****NON-TECHNICAL ABSTRACT****This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). An electron is an elementary particle that carries electric charge and spin (magnetic moment). Abundant in a solid, electrons can interact strongly with each other to bring about novel phenomena when certain conditions are met. Well-known examples of the collective behaviors in strongly correlated electron systems are superconductivity that leads to magnetic levitation and multiferroicity that allows one to control magnetic and electronic properties simultaneously, both of which have potential revolutionary industrial applications. This project will address key issues regarding these phenomena by investigating several exemplary complex oxides. The outcome will advance our understanding of how the spin, charge and crystal lattice are correlated to cause such effects. The research will provide important information on how to better engineer the properties for future technical applications. Undergraduate and graduate students will be trained in state-of-the-art crystal growth and characterization techniques at several international top research institutes, and will have opportunities to develop their own international research network.