钙钛矿锰氧化物外延界面的输运和光电性质及其外场调控

项目名称： 钙钛矿锰氧化物外延界面的输运和光电性质及其外场调控

项目编号： No.11504432

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 尼浩

作者单位： 中国石油大学（华东）

项目金额： 23万元

中文摘要： 钙钛矿氧化物的外延界面是关联电子系统和低维物理的结合，蕴含丰富的物理现象，具有广阔的应用前景。本项目中，我们拟运用原子尺度外延生长技术，制备几个/几十个原胞层厚的钙钛矿锰氧化物异质结的外延界面结构，研究异质结界面的电子输运和光电性质。首先，研究界面外延原胞层数对界面电子输运和光电性质的调制，分析界面效应、尺寸效应、晶格应变所带来的物性变化。其次，研究构成界面的衬底终止离子面、晶面和成分对输运性质的影响，分析电子态和能带特征，探索界面的能带重构机制。最后，利用锰氧化物独特的磁性和输运特性，研究室温条件下，外场（磁场、电场、脉冲电流）对界面的电子输运和光电性质的调控，探究调控机制，实现室温下功能特性的调控增强。通过三方面的研究，阐释锰氧化物界面精细结构与材料性能之间关系和界面能带的重构机制，为实现功能导向的结构设计奠定基础，为实现室温条件下材料器件的开发提供新的途径。

中文关键词： 钙钛矿锰氧化物；异质结界面；电子输运性质；光电特性；外场

英文摘要： Due to combination of strongly correlated electron system and low-dimensional physics, epitaxial interfaces of perovskite oxides have rich physical phenomena and broad applications. In this project, we will fabricate fine interface structures by depositing several/dozens of perovskite-type manganese oxide unit cell layers based on the atomic layer epitaxial deposition techniques, and systematically study the transport and photoelectric properties of the interfaces. Firstly, we will study the transport and photoelectric properties of the interfaces with different thickness and analyze physical properties brought by interface effect, size effect and lattice strain. Secondly, the transport properties of the interfaces fabricated by the substrates with different termination of the ion surface, crystal plane and chemical composition will be systematically studied. Theoretical researches on the rebuild mechanism of the energy band at the interface will be done. Due to their unique magnetic and transport properties of manganese oxides, the external field (magnetic field, electric field and pulsed current) modulation of transport and photoelectric properties will be studied in room temperature. In order to implement practical applications, the mechanism of modulations effect will be carefully analyzed. Through these researches, we will elucidate the relationship between fine structure of the interfaces and functional performance in theory and the rebuild mechanism of the energy band at the interface, which will lay the foundation of the function-oriented design of the device microstructures and a new way to design high performance manganese oxides devices at room temperature.

英文关键词： perovskite-type manganese oxide;heterojunction interface;transport property;photoelectric characteristic;external field