Theory of Metal-Insulator Transitions in Strongly Correlated Electronic Systems with Disorder

9974311 dobrosavljevic1这笔拨款将支持金属-绝缘体跃迁理论的理论研究，重点是结合强电子-电子相互作用和无序。无序相互作用电子的动态平均场方法，先前已应用于过渡金属氧化物，重费米子系统和近道绝缘体，将扩展到处理具有强无序和强相关性的金属-绝缘体转变。这种方法将为问题提供一个简单的有序参数描述，并将用于构建热力学和输运性质的状态方程，这些方程适用于广泛的温度范围、载流子浓度和无序量。在此框架内，将研究涉及莫特-安德森跃迁附近输运、强无序金属中的非费米液体行为、高温异常以及玻璃态行为对金属绝缘跃迁的影响的具体问题。结果将与许多系统直接相关，包括掺杂半导体，无序重费米子系统，层状钌酸盐和锰酸盐，二维电子气体和高温超导体。近年来，人们对金属-绝缘体跃迁这个长期存在的问题重新产生了兴趣，Mott和Anderson的传统模型分别强调了电子相关和局部无序的作用。许多具有技术意义的新材料都具有电子性质，它们既表现出强的电子-电子相互作用，又表现出无序性，这很难用传统的理论工具来分析。这项资助支持一种新方法的开发和应用研究，这种方法可以结合这两个相关过程。这项工作将为该问题提供一个简单的有序参数描述，并将用于构建热力学和输运性质的状态方程，该方程适用于广泛的温度范围、载流子浓度和无序量。这种方法应该可以结合所有的基本定位机制，包括莫特和安德森路线，以及电子玻璃冻结的可能性。结果将与许多系统直接相关，包括掺杂半导体，无序重费米子系统，层状钌酸盐和锰酸盐，二维电子气体和高温超导体。这种形式主义可以适应许多现实情况，为材料科学研究的发展开辟了新的途径。

9974311DobrosavljevicThis grant will support theoretical research into a theory of metal-insulator transitions, with an emphasis on incorporating both strong electron-electron interactions and disorder. A dynamical mean-field approach to disordered interacting electrons, which has previously been applied to transition-metal oxides, heavy-fermion systems, and Kondo insulators, will be extended to treat metal-insulator transitions with strong disorder and strong correlations. This approach will provide a simple order-parameter description of the problem, and will be used to construct equations of state for thermodynamic and transport properties valid over a broad range of temperatures, carrier concentrations, and amounts of disorder. Within this framework, specific problems involving transport near Mott-Anderson transitions, non-Fermi liquid behavior in strongly disordered metals, high temperature anomalies, and the effects of glassy behavior on metal-insulation transitions will be studied. The results will be of direct relevance to many systems, including doped semiconductors, disorder heavy-fermion systems, layered ruthenates and manganites, two-dimensional electron gases, and high-temperature superconductors.Recent years have witnessed renewed interest in a long-standing problem of metal-insulator transitions, with the traditional models of Mott and Anderson emphasizing the roles of electron correlations and local disorder, respectively. Many new materials with technological significance have electronic properties exhibiting both strong electron-electron interactions and disorder, which is difficult to analyze using convention theoretical tools. This grant supports research into the development and application of a new approach that can incorporate both of these relevant processes. This work will provide a simple order-parameter description of the problem, and will be used to construct equations of state for thermodynamic and transport properties valid over a broad range of temperatures, carrier concentrations, and amounts of disorder. This approach should make it possible to incorporate all the basic mechanisms of localization, including both the Mott and Anderson route, as well as the possibility of glassy freezing of electrons. The results will be of direct relevance to many systems, including doped semiconductors, disorder heavy-fermion systems, layered ruthenates and manganites, two-dimensional electron gases, and high-temperature superconductors. The formalism can be adapted to many realistic situations and should open new avenues for the development of materials science research.